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  • USB hard drive not recognized

    - by user318772
    Until recently I was using the portable USB hard drive in my win 7 laptop and ubuntu laptop. Suddenly now none of the laptops recognize it. This is the message i get by doing lsusb... Bus 001 Device 004: ID 1058:1010 Western Digital Technologies, Inc. Elements External HDD Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 003: ID 0b97:7762 O2 Micro, Inc. Oz776 SmartCard Reader Bus 003 Device 002: ID 0b97:7761 O2 Micro, Inc. Oz776 1.1 Hub Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 002 Device 002: ID 413c:a005 Dell Computer Corp. Internal 2.0 Hub Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub fdisk doesn't show the external hard drive Disk /dev/sda: 80.0 GB, 80026361856 bytes 255 heads, 63 sectors/track, 9729 cylinders, total 156301488 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x0004a743 Device Boot Start End Blocks Id System /dev/sda1 * 2048 152111103 76054528 83 Linux /dev/sda2 152113150 156301311 2094081 5 Extended /dev/sda5 152113152 156301311 2094080 82 Linux swap / Solaris when i do testdisk TestDisk 6.14, Data Recovery Utility, July 2013 Christophe GRENIER <[email protected]> http://www.cgsecurity.org TestDisk is free software, and comes with ABSOLUTELY NO WARRANTY. Select a media (use Arrow keys, then press Enter): >Disk /dev/sda - 80 GB / 74 GiB - ST980825AS Disk /dev/sdb - 2199 GB / 2048 GiB testdisk-> Intel->analyse I get partition error Disk /dev/sdb - 2199 GB / 2048 GiB - CHS 2097152 64 32 Current partition structure: Partition Start End Size in sectors Partition: Read error Here is the output of dmesg [11948.549171] Add. Sense: Invalid command operation code [11948.549177] sd 2:0:0:0: [sdb] CDB: [11948.549181] Read(16): 88 00 00 00 00 00 00 00 00 00 00 00 00 08 00 00 [11948.550489] sd 2:0:0:0: [sdb] Invalid command failure [11948.550495] sd 2:0:0:0: [sdb] [11948.550499] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [11948.550505] sd 2:0:0:0: [sdb] [11948.550508] Sense Key : Illegal Request [current] [11948.550514] Info fld=0x0 [11948.550519] sd 2:0:0:0: [sdb] [11948.550525] Add. Sense: Invalid command operation code [11948.550531] sd 2:0:0:0: [sdb] CDB: [11948.550534] Read(16): 88 00 00 00 00 00 00 00 00 00 00 00 00 08 00 00 [11948.551870] sd 2:0:0:0: [sdb] Invalid command failure [11948.551876] sd 2:0:0:0: [sdb] [11948.551880] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [11948.551885] sd 2:0:0:0: [sdb] [11948.551888] Sense Key : Illegal Request [current] [11948.551895] Info fld=0x0 [11948.551900] sd 2:0:0:0: [sdb] [11948.551905] Add. Sense: Invalid command operation code [11948.551911] sd 2:0:0:0: [sdb] CDB: [11948.551914] Read(16): 88 00 00 00 00 00 00 00 00 00 00 00 00 08 00 00 If possible i want to retrive at least some data from this hard drive. If thats not possible I would like to format it and use it. Any help will be greatly appreciated Thanks

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  • Display is slightly blurry on (native) 1920x1080 resolution

    - by Martin Tuskevicius
    I have a computer monitor that is approximately 23" in size. Its native resolution is 1920x1080, and Windows 7 will not allow it to be any higher. However, I cannot make the resolution a little lower as well. When I right-click on my desktop and select 'Screen resolution,' the vertical slider has only two options: 1920x1080 and 1280x720. There are no real problems that I am having besides the fact that the image is slightly blurry. I can easily make things out and see them, but I definitely feel that the image is not as clear as it could be. My graphics card is ATI Radeon HD 5450 and it has the latest graphics drivers installed. I've tried playing around with the AMD VISION Engine Control Center to see if I can change an option to make the image clearer, but I had no luck. I did find one odd thing, though. When I lowered the refresh rate from 60Hz to 50Hz, the image kind of "zoomed in" but it also became perfectly clear like I would expect it to look. The problem is that when I use 50Hz, the image zooms in a little on the center and I lose maybe an inch and a half of the screen (I do not see the bar at the top of applications, I do not see the Windows taskbar thing, etc). I figured if I could somehow zoom in so that the entire image fills the screen (not the slightly cropped version) then I would have the perfectly crisp image of 50Hz, and also the uncropped image of 60Hz. However, upon zooming in, the image began to look blurry again just like it did with 60Hz. So I am at a loss here. I do not know how to make the image look as clear as it should. I have the latest drivers (I updated them today) and I know that my monitor supports the resolution that I am trying to use. Has anybody experienced something like this before? I'd really appreciate any input - thanks! Update: I have figured out how to make the display look crisp! I set it to the 50Hz option, and then I changed the scaling through the monitor itself, rather than software. Now, however, I am finding that games look pretty bad because since it is clear, the lower quality really becomes apparent. I cannot run new games at 1080p, so I run them at the lowest resolution possible (1280x720, since it is the only other option offered, as I have mentioned). So I am wondering, is there a way to have Windows display more resolution options?

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  • Network speeds being report as 4x higher than actual in Windows 7 SP1

    - by Synetech
    Ever since installing Windows 7 SP1, I have noticed that all programs that display my network transfer rate have been exactly 4x higher than they actually are. For example, when I download something from a high-bandwidth web site or through torrents with lots of sources, the download rate indicated is is ~5MBps (~40Mbps) even though my Internet connection has a maximum of only 1.5MBps (12Mbps). It is the same situation with the upstream bandwidth: the connection maximum is 64KBps, but I’m seeing up to 256KBps. I have tried several different programs for monitoring bandwidth throughput and they all give the same results. I also tried different times and different days, and they always show the rate as being four times too high. My initial thought was that my ISP had increased the speeds (without my noticing), which they have done before. However, I checked my ISP’s site and they have not increased the speeds. Moreover, when I look at the speeds in the program actually doing the transfer (eg Chrome, µTorrent, etc.), the numbers are in line with the expected values at the same time that bandwidth monitoring programs are showing the high numbers. The only significant change (and pretty much the only change at all) that has occurred to my system since the change was the installation of SP1 for Windows 7. As such, it is my belief that some sort of change exists in SP1 whereby software that accesses the bandwidth via a specific API receives (erroneously?) high numbers while others that have access to the raw data continue to receive the correct values. I booted into Windows XP and downloaded some things via HTTP and torrent and in both cases, the numbers were as expected (like they were in Windows 7 before installing SP1). I then booted back into 7SP1 and once again, the numbers were four times higher than possible. Therefore it is definitely something in SP1 that has changed how local bandwidth is calculated/returned. There is definitely something wonky with Windows 7 SP1’s network speed calculation. I tried Googling this, but (for multiple reasons), have had a difficult time finding anything relevant. Has anybody else noticed this behavior? Does anybody know of any bugs or changes in SP1 that could account for it?

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  • Recovering damaged external hard disk by installing internally

    - by nfarshchi
    I had a 1TB Western Digital (My book series) 3.5" USB3. One day, the SATA to USB3 converter board was damaged and has not worked since. I decided to open the cover and use the HDD as an internal HDD. When I attached the HDD to my PC and booted up in Windows, it asked me which type of ????? I want to use "MBR or GBR" (I dont remember the exact question) I chose MBR and Windows gave me a 1TB empty Hard drive. I tried to recover with recover my files and some other recovery programs but no success. Some one told me that you should choosed GBR instead of MBR . How can I do that now? Another guy told me that the SATA to USB3 converter board is coded to save data on HDD and you can not use them internally without losing data, and I should find another SATA to USB3 board (exact same). It is impossible to find because they are not produced any more. Please help me to find a solution to bring back my data. UPDATE I have 1TB WD "Mybook" USB 3. the board that convert sata to usb3 was damaged. so when the HDD was in the box computer did not recognize it. I opened the box and remove HDD to use it internal. after connecting to my PC windows showed me one massage that I had two choice MBR or GPT I choosed MBR one and windows gave me 1TB empty new volume. I tried many recovery software to recover my data but no success. I brought it to one expert recovery company and they told me the converter board (SATA to USB3) make some encryption on data and with out that board you cannot recover any thing. so I bought another empty WD box and put the HDD inside but even after that also there is no file. I tried to recover again in this state but no success. so I have some unanswered question. does this converted boards make any password or encryption? if yes how can I solve it? does using many recovery programs affected my data? any suggestion or solution for bring back my data? I had use recovery programs such as : recover my files , EaseUS data recovery, easy recovery, test disk, Ontrack easy recovery . Note: when I was using test disk it asked me to choose which partition table I want to use. as it was I choose NTFS, does this made any change on data?

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  • OpenSSH (Windows) does not forward X11

    - by Shulhi Sapli
    I'm running Ubuntu 13.04 in VM and I wanted to do X11 forwarding to my host (Win 8), so far it works fine using PuTTY and XMing server for Windows. But I am curious why it doesn't work if I use OpenSSH binaries (it comes together with Git for windows). This is what I've done so far: ssh -X [email protected] (also tried with -Y) then gedit but received error of Cannot open display. echo $DISPLAY came out as empty. So, I try to export DISPLAY=localhost:0.0 but it still won't work. The DISPLAY environment that I set is exactly as when it runs with Putty. I also try changing the DISPLAY to 192.168.2.3:0.0 and other display number as well, but still it won't work. Of course I could just use Putty to make it work, but I was wondering why OpenSSH binaries does not work. I have enabled all settings required in both /etc/ssh/ssh_config and /etc/ssh/sshd_config. If I run with -v option, this is what I get F:\SkyDrive\Projects> ssh -X -v [email protected] OpenSSH_4.6p1, OpenSSL 0.9.8e 23 Feb 2007 debug1: Connecting to 192.168.2.3 [192.168.2.3] port 22. debug1: Connection established. debug1: identity file /c/Users/Shulhi/.ssh/identity type -1 debug1: identity file /c/Users/Shulhi/.ssh/id_rsa type -1 debug1: identity file /c/Users/Shulhi/.ssh/id_dsa type -1 debug1: Remote protocol version 2.0, remote software version OpenSSH_6.1p1 Debian-4 debug1: match: OpenSSH_6.1p1 Debian-4 pat OpenSSH* debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_4.6 debug1: SSH2_MSG_KEXINIT sent debug1: SSH2_MSG_KEXINIT received debug1: kex: server->client aes128-cbc hmac-md5 none debug1: kex: client->server aes128-cbc hmac-md5 none debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP debug1: SSH2_MSG_KEX_DH_GEX_INIT sent debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY debug1: Host '192.168.2.3' is known and matches the RSA host key. debug1: Found key in /c/Users/Shulhi/.ssh/known_hosts:2 debug1: ssh_rsa_verify: signature correct debug1: SSH2_MSG_NEWKEYS sent debug1: expecting SSH2_MSG_NEWKEYS debug1: SSH2_MSG_NEWKEYS received debug1: SSH2_MSG_SERVICE_REQUEST sent debug1: SSH2_MSG_SERVICE_ACCEPT received debug1: Authentications that can continue: publickey,password debug1: Next authentication method: publickey debug1: Trying private key: /c/Users/Shulhi/.ssh/identity debug1: Trying private key: /c/Users/Shulhi/.ssh/id_rsa debug1: Next authentication method: password [email protected]'s password: It seems that there is no request for X11 (I'm not sure if there is should be one too here). Any pointers why it doesn't work?

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  • How to install RAID drivers on already installed Windows 7?

    - by happysencha
    64-bit Windows 7 Ultimate 6GB RAM Intel i7 920 Intel X25-M SSD 80GB 2,5" Club 3D Radeon HD5750 GA-EX58-UD4P Motherboard I've been running fine with Windows 7 installed on the SSD. I wanted to create an mirrored Raid-1 setup for backups using two hard disks, so I ordered two Samsung HD203WI. This motherboard supports two different RAID controllers, the Intel's ICH10R and Gigabyte's SATA2 SATA controller. There are 6 SATA ports behind the ICH10R and 2 SATA ports for the Gigabyte controller. I googled around and seemed that the ICH10R is a better choice and since then I've been trying to make it work. When I activate the [RAID] mode from BIOS, the Windows 7 gives BSOD exactly as described by this guy: "Windows 7 will start to boot, it gets to the screen where there are 4 colors coming together and it blue screens and restarts no matter what I do." First thing I did: turned off the RAID and booted to Windows and tried to install the SATA RAID drivers from Gigabyte. I launch the driver installation program and it gives "This computer does not meet the minimum requirements for installing the software" error. I then tried Intel's Rapid Storage Technology drivers (which apparently is the same as the one offered at Gigabyte's site), but it resulted in exactly the same error. I then detached the new Samsung hard disks from the SATA ports, but left the [RAID] enabled in BIOS. To my surprise, it still BSOD'd, so at this point I knew it is an OS/driver issue. Also, I tried with the Gigabyte's RAID enabled (while the ICH10R RAID disabled) and it booted just fine. So then I thought, that maybe I can't install the RAID drivers from within the OS. So I caused the BSOD on purpose once again, and then with ICH10R RAID activated and Samsung hard disks attached, I choose the Windows 7 Recovery mode in the boot menu. It sees some problem(s), tries to repair, does not succeed and does not ask for drivers (which I put on a USB stick) to install. I also tried to use the command-line in the recovery: "rundll32 syssetup, SetupInfObjectInstallAction DefaultInstall 128 iaStor.inf" but it gave "Installation failed." So I'm clueless how should I proceed. Do I really need to re-install Windows 7 and load RAID drivers in the Win7 setup? I don't want to install any OS on the RAID, the Windows 7 is and will be on the SSD. I just want to have a RAID-1 backup using those two hard disks. I mean why would I need to re-install operating system to add RAID setup?

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  • VLAN issues between linux kernels 2.6 / 3.3 in an ESX / Cisco environment

    - by David Griffith
    I shall attempt to explain an issue I have encountered - I have a VM running on esx 4.1 with an interface connected to VLAN800 via an access port on a cisco 3750. It runs linux - kernel 2.6.24, and has about 5 to 10 Mbit of chatter on 10.10.0.0/16 and various multicast addresses to look after. I needed to isolate certain devices from certain other devices on the network, with all of them having to talk to that one VM. No, the address space can't be separated, nor can the networks be easily vlan'd apart. The software on the VM listens to one interface only. Private vlans appear to be the way to go. So as a test, I built a bridge on the VM that globs together the vlans as needed. All good, everything works as expected. But occasionally (sigh) there's some latency that trips up a couple of profinet devices on the network because, you know, you're not really supposed to trunk real-time protocols around the place willy-nilly. I shift it to our test/backup server - works nicely, but I don't want it to be running on the test server as we muck around with that a lot. So I says to myself, "I'll put it on a new VM for testing and tweaking." I download a small linux distro with kernel 3.3, and install as a new VM with a the vlans as separate interfaces for testing. I power up the testing VM - ok. I bring up all the separate interfaces - ok. I can ping the production VM, see all sorts of traffic going past with tshark, etc. I build a bridge and put the primary vlan on it - the production VM running 2.6 immediately loses its multicast traffic - Unicast is fine. (?) I shut down the bridge - still no multicast traffic (!?) I power-cycle the production VM(!?!?) - multicast traffic returns. I trunk everything into the testing VM and create vlan interfaces under linux instead - same result, as soon as I start the bridge.... no multicast on the production VM. Ok, so I take a break and leave things alone. I decide to play with a couple of ubiquiti bullet radios - I'm testing various firmware as a side project. I flash a radio with Open-wrt-12.09. I enable a trunk on a port on a cisco on our network so I can muck around with multiple vlans and SSIDs I power up the radio and connect - ok. I create a vlan interface from the trunk.... the same vlan as the production VM wayyyyy over there, three cisco routers away. Ok. I bridge the vlan interface to the wifi interface and immediately get a phone call. The production VM has (suprise!) lost its multicast traffic. Again, nothing comes back until I power-cycle the VM. What the hell is going on?

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  • Why isn't passwordless ssh working?

    - by Nelson
    I have two Ubuntu Server machines sitting at home. One is 192.168.1.15 (we'll call this 15), and the other is 192.168.1.25 (we'll call this 25). For some reason, when I want to setup passwordless login from 15 to 25, it works like a champ. When I repeat the steps on 25, so that 25 can login without a password on 15, no dice. I have checked both sshd_config files. Both have: RSAAuthentication yes PubkeyAuthentication yes I have checked permissions on both servers: drwx------ 2 bion2 bion2 4096 Dec 4 12:51 .ssh -rw------- 1 bion2 bion2 398 Dec 4 13:10 authorized_keys On 25. drwx------ 2 shimdidly shimdidly 4096 Dec 4 19:15 .ssh -rw------- 1 shimdidly shimdidly 1018 Dec 4 18:54 authorized_keys On 15. I just don't understand when things would work one way and not the other. I know it's probably something obvious just staring me in the face, but for the life of me, I can't figure out what is going on. Here's what ssh -v says when I try to ssh from 25 to 15: ssh -v -p 51337 192.168.1.15 OpenSSH_5.9p1 Debian-5ubuntu1, OpenSSL 1.0.1 14 Mar 2012 debug1: Reading configuration data /etc/ssh/ssh_config debug1: /etc/ssh/ssh_config line 19: Applying options for * debug1: Connecting to 192.168.1.15 [192.168.1.15] port 51337. debug1: Connection established. debug1: identity file /home/shimdidly/.ssh/id_rsa type 1 debug1: Checking blacklist file /usr/share/ssh/blacklist.RSA-2048 debug1: Checking blacklist file /etc/ssh/blacklist.RSA-2048 debug1: identity file /home/shimdidly/.ssh/id_rsa-cert type -1 debug1: identity file /home/shimdidly/.ssh/id_dsa type 2 debug1: Checking blacklist file /usr/share/ssh/blacklist.DSA-1024 debug1: Checking blacklist file /etc/ssh/blacklist.DSA-1024 debug1: identity file /home/shimdidly/.ssh/id_dsa-cert type -1 debug1: identity file /home/shimdidly/.ssh/id_ecdsa type -1 debug1: identity file /home/shimdidly/.ssh/id_ecdsa-cert type -1 debug1: Remote protocol version 2.0, remote software version OpenSSH_5.9p1 Debian-5ubuntu1 debug1: match: OpenSSH_5.9p1 Debian-5ubuntu1 pat OpenSSH* debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_5.9p1 Debian-5ubuntu1 debug1: SSH2_MSG_KEXINIT sent debug1: SSH2_MSG_KEXINIT received debug1: kex: server->client aes128-ctr hmac-md5 none debug1: kex: client->server aes128-ctr hmac-md5 none debug1: sending SSH2_MSG_KEX_ECDH_INIT debug1: expecting SSH2_MSG_KEX_ECDH_REPLY debug1: Server host key: ECDSA 54:5c:60:80:74:ab:ab:31:36:a1:d3:9b:db:31:2a:ee debug1: Host '[192.168.1.15]:51337' is known and matches the ECDSA host key. debug1: Found key in /home/shimdidly/.ssh/known_hosts:2 debug1: ssh_ecdsa_verify: signature correct debug1: SSH2_MSG_NEWKEYS sent debug1: expecting SSH2_MSG_NEWKEYS debug1: SSH2_MSG_NEWKEYS received debug1: Roaming not allowed by server debug1: SSH2_MSG_SERVICE_REQUEST sent debug1: SSH2_MSG_SERVICE_ACCEPT received debug1: Authentications that can continue: publickey,password debug1: Next authentication method: publickey debug1: Offering RSA public key: /home/shimdidly/.ssh/id_rsa debug1: Authentications that can continue: publickey,password debug1: Offering DSA public key: /home/shimdidly/.ssh/id_dsa debug1: Authentications that can continue: publickey,password debug1: Trying private key: /home/shimdidly/.ssh/id_ecdsa debug1: Next authentication method: password

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  • Switching efficiently between windows, not apps, in OS X

    - by Vultan
    Previous questions have asked "how can I efficiently switch between windows, not applications, in OS X"? (Switching windows on OS X, Switch between windows on Mac OS X? and others). The most recommended suggestions seem to be: Use some combo of cmd-tab and cmd-~. Use Expose, and possibly Spaces Use Witch I spent the money on Witch, and have been using it for a few weeks; it's ok, but it is sometimes slow to respond, sometimes buggy on window order, crashes my system if I disable and re-enable it too many times, and doesn't work properly with X11 apps. The built-in cmd-tab and cmd-~ are ok, but still bring an entire application to the forefront. I find a very common workflow I use is to bounce back and forth between two windows (for example, a browser window and a Thunderbird email in progress), when both apps (the browser and email software) have multiple windows open. I can use Cmd-Tab to get back and forth between apps, but whenever I switch to an app, ALL windows from that app pop up. That suddenly fills my screen with irrelevant data and windows, and often drops those other windows in front of the single window from the other app that I was using and would conveniently like to keep viewing even though it isn't in focus. Expose seems to be the preferred "OS X natural way," but I can't seem to get myself to use it efficiently. I hit F9, and see 10 windows; I then need to squint, try to find the window I want, then use the mouse or the cursor keys to navigate to the one I want. Given the number of power users who say they use Expose, I must be missing the boat here. My goal is not to make this a repeat of previous questions. I'm not asking "what are my alternatives?" (unless I've missed one above!) Rather, I'm asking: what are you, OS X power users, actually doing to handle the use case I described above? Another common use case for me is having multiple Excel spreadsheets open and multiple browser windows open, and I'm rapidly switching back and forth between one spreadsheet in particular and one browser window. Every time I Cmd-Tab, all spreadsheets or all browser windows appear: I don't want to see the ones I'm not working with, and they tend to hide the windows from the alternative app that I don't have in focus but I'd like to at least eyeball. Can you describe what your workflow is like, and how you rapidly and thoughtlessly switch between windows from apps that have multiple windows open?

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  • Remote Debian System Preventing Logon

    - by choobablue
    I have a dozen or so single board computers on a network running Debian (squeeze) and access them via ssh (ssh server is dropbear). To give an idea of the hardware of these computers they're 1.2 GHz x86 processors, 1GB of RAM and 4GB flash drives formatted as ext2 (I avoided ext3 to prevent the added flash write stress from journaling), there is also a swap partition on the drive. Normally the setup I'm using works great and I can access all the computers. Every once in a while one will prevent access. What happens is I try to connect via ssh (putty) and it gives me the login prompt, I enter the username and password and it responds 'Access Denied' and it will also refuse any public key in ~/.ssh/authorized_keys. The credentials are correct as they worked previously. The computer responds to pings and putty recognizes the server public key, which implies to me the system is still running. Restarting the server fixes the problem and I can log in again. (I tried a temporary fix of putting shutdown -r now in the root crontab but this doesn't seem to reliably be run once the hang happens) Once I restart however there doesn't seem to be any information in any of the system logs to indicate what happened, the logs are simply empty for that time period, as if the system had crashed. There is some custom software running on the system which appears to stop working (which is why I wanted to ssh to begin with). I'm assuming that this program is the source of the problems but I'm unsure of how it would cause it and how to debug what is happening. The most likely explanation I can think of is that there is a memory leak in the other program that then prevents dropbear from spawning a new login shell (and crontab from executing shutdown) as there is not enough free memory. But looking at memory usage of the other (working) computers there doesn't seem to be any meaningful increase in memory to indicate a leak (unless it's a very big, fast acting and rare leak). I would think that when the OS ran out of memory it would restart the system or kill processes (the Linux kernel restarts right?). The other thing I wonder about is if the fact that they are running off a flash drive could have some effect, especially the swap partition (which I think I should remove to prevent wear of the flash), but the flash drives are young (~1 month) and I don't think that wear would be a factor yet. Does anybody have an idea of what could cause these symptoms, if it could be done by a memory leak, or something else I haven't thought of. And does anybody know of a method to try to debug the problem and find out more information about what's going wrong?

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  • Wifi network stopped being visible (and usable) (Linksys wag320n)

    - by s427
    Basically, my wifi network simply stopped working for no apparent reason. It doesn't appear in the list of the available networks anymore. I can see all my neighbors' networks, but not mine. It's as if it doesn't exist anymore. The internet connection (non-wifi), which goes through the same modem/router, is fine though. I already had a similar problem about one year ago (see here: Wifi network SSID not visible ), just after buying this very modem. I finally got it to work after performing two factory resets and getting rid of the Cisco "Magic" software; but this time it's not working. I use a linksys router-modem (WAG320N) which is directly connected (via network cable) to my desktop computer (Windows 7). I have (mainly) two devices that use the wifi network: my phone (Samsung Galaxy Nexus) and an Asus tablet (TF201, aka Transformer Prime). I also resurrected an old laptop computer (Dell, running Windows XP) to test that, and it doesn't see anything either (apart from the 20 other wifi networks, of course ^^). This wifi network was working just fine and has been for about a year. I haven't touched the modem settings so I have no idea what's causing the problem. I tried: making my phone "forget" about my network, hoping it would see it again after that: no luck. re-entering the network informations (SSID/password) manually on my phone: still no luck (says it's not in range) exporting the modem configuration, resetting the modem (factory reset, via modem admin), restarting it, importing the configuration: nope. factory reset, turning it off for 15 minutes, restarting, re-factory reset, and entering the configuration manually: still nothing. Has anybody experienced something similar before? Have you any suggestion to fix that? Thanks in advance. PS: to clear things up, here are the settings of my modem regarding wifi: Basic wireless settings: Configuration: manual Radio Band: 2.4GHz Wireless Network Mode: B/G/N-Mixed SSID: s427 Channel Bandwidth: Wide - 40 MHz Channel Wide Channel: 9 - 2.452GHz Standard Channel: 11 - 2.462GHz SSID Broadcast: Enable Advanced Wireless Settings AP Isolation: Disable Authentication Type: Auto Basic Rate: Default Transmission Rate: Auto N Transmission Rate: Auto CTS Protection Mode: Disable Beacon Interval: 100 DTIM Interval: 1 Fragmentation Threshold: 2346 RTS Threshold: 2346

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  • mdadm raid1 fails to resync

    - by JuanD
    Hello, I'm trying to solve this problem I'm having with an mdadm raid1. I have an ubuntu 9.04 server running on a software 2-drive raid1 with mdadm. Yesterday, one of the drives failed, and so I replaced it with a brand new drive of the same size. I removed the faulty drive, copied the partition from the remaining good drive to the new drive and then added it to the raid. It re-synced and the system worked fine, until the drive that hadn't failed, was also labeled failed. Now I had the raid running solely on the new drive. So I purchased another drive and repeated the procedure above. So now I had 2 brand new drives and the raid was syncing. However, after a few minutes I checked /proc/mdstat and the raid was no longer syncing. mdadm --detail /dev/md1 shows: (sdb is the first new drive, and sdc is the second new drive) root@dola:/home/jjaramillo# mdadm --detail /dev/md1 /dev/md1: Version : 00.90 Creation Time : Sat Dec 20 00:42:05 2008 Raid Level : raid1 Array Size : 974711680 (929.56 GiB 998.10 GB) Used Dev Size : 974711680 (929.56 GiB 998.10 GB) Raid Devices : 2 Total Devices : 2 Preferred Minor : 1 Persistence : Superblock is persistent Update Time : Wed Jun 2 10:09:35 2010 State : clean, degraded Active Devices : 1 Working Devices : 2 Failed Devices : 0 Spare Devices : 1 UUID : bba497c6:5029ba0b:bfa4f887:c0dc8f3d Events : 0.5395594 Number Major Minor RaidDevice State 2 8 35 0 spare rebuilding /dev/sdc3 1 8 19 1 active sync /dev/sdb3 I've tried removing and re-adding the drive a few times, but the same thing happens. The raid fails to resync. I've looked at /var/log/messages, and found the following: Jun 2 07:57:36 dola kernel: [35708.917337] sd 5:0:0:0: [sdb] Unhandled sense code Jun 2 07:57:36 dola kernel: [35708.917339] sd 5:0:0:0: [sdb] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE Jun 2 07:57:36 dola kernel: [35708.917342] sd 5:0:0:0: [sdb] Sense Key : Medium Error [current] [descriptor] Jun 2 07:57:36 dola kernel: [35708.917346] Descriptor sense data with sense descriptors (in hex): Jun 2 07:57:36 dola kernel: [35708.917348] 72 03 11 04 00 00 00 0c 00 0a 80 00 00 00 00 00 Jun 2 07:57:36 dola kernel: [35708.917357] 00 43 9e 47 Jun 2 07:57:36 dola kernel: [35708.917360] sd 5:0:0:0: [sdb] Add. Sense: Unrecovered read error - auto reallocate failed So it looks like there's some kind of error on sdb (the first new drive). My question is, what would be the best approach to get the raid up and running again? I've thought about dd'ing the /dev/md1 to a blank hard drive, then re-doing the raid from scratch and loading the data back, but there could be an easier solution.. Any help would be appreciated.

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  • 2 servers, high availability and faster response

    - by user17886
    I recently bought a second webserver because I worry about hardware failure of my old server. Now that I have that second server I wish to do a little more then just have one server standby and replicate all day. As long as it's there I might as well get some advantage our of it ! I have a website powered by ubuntu 12.04, nginx, php-fpm, apc, mysql (5.5) and couchdb. Im currently testing configurations where i can achieve failover AND make good use of the extra harware for faster responses / distributed load. The setup I am testing nowinvolves heartbeat for ip failover and two identical servers. Of the two servers only one has a public ip adress. If one server crashes the other server takes over the public ip adress. On an incoming request nginx forwards the request tot php-fpm to either server a of server b (50/50 if both servers are alive). Once the request has been send to php-fpm both servers look at localhost for the mysql server. I use master-master mysql replication for this. The file system is synced with lsyncd. This works pretty well but Im reading it's discouraged by the (mysql) community. Another option I could think of is to use one server as a mysql master and one server as a web/php server. The servers would still sync their filesystem, would still run the same duplicate software (nginx,mysql) but master slave mysql replication could be used. As long as bother servers are alive I could just prefer nginx to listen to ip a and mysql to ip b. If one server is down, the other server could take over the task of the other server, simply by ip switching. But im completely new at this so I would greatly value your expert advice. Is either of the two setups any good ? If you have any thoughts on this please let me know ! PS, virtualisation, hosting on different locations or active/passive setups are not solutions im looking for. I find virtual server either too slow or too expensive. I already have a passive failover on another location. But in case of a crash I found the site was still unreachable for too long due to dns caching.

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  • [CentOS 4.8] nslookup resolves domains to IPs, but I can't get a response to pings to external servers

    - by Beco
    I have a fresh install of CentOS 4.8 running on an internal development server. I haven't done anything to it besides setting up sudoers and SSH. I can SSH into the server and from there resolve domains to IPs and ping internal servers, but for some reason I don't get any response from pinging external servers. The software firewall is disabled, and the problem is present with both static and DHCP-assigned network configurations. The network domain controller is a Windows Server 2003 box. $ nslookup google.com Server: 10.254.2.5 Address: 10.254.2.5#53 Non-authoritative answer: Name: google.com Address: 74.125.47.147 Name: google.com Address: 74.125.47.99 <etc...> 10.254.2.5 is the Win2K3 server. $ ping google.com PING google.com (74.125.47.106) 56(84) bytes of data. It just hangs here indefinitely. $ cat /etc/resolv.conf ; generated by /sbin/dhclient-script search <...snip...>.local nameserver 10.254.2.5 nameserver 10.254.2.124 10.254.2.124 is the backup DC server, which is currently off and tombstoned by this point. The snipped section is our company name. # ifconfig eth0 Link encap:Ethernet HWaddr <snip> inet addr:10.254.2.101 Bcast:10.254.2.255 Mask:255.255.255.0 inet6 addr: <snip>/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:80066 errors:0 dropped:0 overruns:0 frame:0 TX packets:4421 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:7810133 (7.4 MiB) TX bytes:590550 (576.7 KiB) Interrupt:225 Base address:0xc000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:32 errors:0 dropped:0 overruns:0 frame:0 TX packets:32 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:8104 (7.9 KiB) TX bytes:8104 (7.9 KiB) # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 10.254.2.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth0 0.0.0.0 10.254.2.5 0.0.0.0 UG 0 0 0 eth0 And, for good measure, a snapshot of the current ethernet config via the system-config-network GUI. Edit: I don't yet have enough rep to post images, so here's a link. Sorry! system-config-network snapshot I'm pretty green when it comes to setting up *nix dev servers and network configuration in general, so please let me know if I've left out critical information, or posted information I shouldn't have posted. Thanks!

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  • How to Create Auto Playlists in Windows Media Player 12

    - by DigitalGeekery
    Are you getting tired of the same old playlists in Windows Media Player? Today we’ll show you how to create dynamic auto playlists based on criteria you choose in WMP 12 in Windows 7. Auto Playlists In Library view, click on Create playlist dropdown arrow and select Create auto playlist. On the New Auto Playlist window type in a name for the playlist in the text box. Now we need to choose our criteria by which to filter your playlist. Select Click here to add criteria. For our example, we will create a playlist of songs that were added to the library in the last week from the Alternative genre. So, we will first select Date Added from the dropdown list. Many criteria will have addition options to configure. In the example below you will see that we have a few options to fine tune.   We will filter all the songs added to the library in the last 7 days. We will select Is After from the first dropdown list. Then select Last 7 Days from the second dropdown list. You can add multiple criteria to further filter your playlist. If you can’t find the criteria you are looking for, select “More” at the bottom of the dropdown list.   This will pull up a filter window with all the criteria. Select a filter and then click OK when finished.   From the Genre dropdown, we will select Alternative. If you’d like to add Pictures, Videos, or TV Shows to your auto playlists you can do so by selecting them from the dropdown list under And also include. You will then be able to select criteria for your pictures, videos, or TV shows from the dropdown list.   Finally, you can also add restrictions to your music such as the number of items, duration, or total size. We will limit the duration of our playlist to one hour by selecting Limit Total Duration To… Then type in 1 hour…Click OK.   Our library is automatically filtered and a playlist is created based on the criteria we selected. When additional songs are added to the Windows Media Player library, any of new songs that fit the criteria will automatically be added to the New Songs playlist. You can also save a copy of an auto playlist as a regular playlist. Switch to Playlists view by clicking Playlists from either the top menu or the navigation bar. Select the Play tab and then click Clear list to remove any tracks from the list pane.   Right-click on the playlist you want to save, select Add to, and then Play list. The songs from your auto playlist will appear as an Unsaved list on the list pane. Click Save list. Type in a name for your playlist. Your auto playlist will continue to change as you add or remove items from your Media Player library that meet the criteria you established. The new saved playlist we just created will stay as it is currently. Editing a Auto playlist is easy. Right-click on the playlist and select Edit. Now you are ready to enjoy your playlist. Conclusion Auto playlists are great way to keep your playlists fresh in Windows Media Player 12. Users can get creative and experiment with the wide variety of criteria to customize their listening experience. If you are new to playlists in Windows Media Player, you may want to check our our previous post on how to create custom playlists in Windows Media Player 12. Are you looking to get better sound from WMP 12? Take a look at how to improve playback using enhancements in Windows Media Player 12. Similar Articles Productive Geek Tips Create Custom Playlists in Windows Media Player 12Fixing When Windows Media Player Library Won’t Let You Add FilesInstall and Use the VLC Media Player on Ubuntu LinuxMake Windows Media Player Automatically Open in Mini Player ModeMake VLC Player Look like Windows Media Player 10 TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips VMware Workstation 7 Acronis Online Backup DVDFab 6 Revo Uninstaller Pro Error Goblin Explains Windows Error Codes Twelve must-have Google Chrome plugins Cool Looking Skins for Windows Media Player 12 Move the Mouse Pointer With Your Face Movement Using eViacam Boot Windows Faster With Boot Performance Diagnostics Create Ringtones For Your Android Phone With RingDroid

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  • Looking For iPhone 4S Alternatives? Here Are 3 Smartphones You Should Consider

    - by Gopinath
    If you going to buy iPhone 4S on a two year contract in USA, Europe or Australia you may not find it expensive. But if you are planning to buy it in any other parts of the world, you will definitely feel the heat of ridiculous iPhone 4S price. In India iPhone 4S costs approximately costs $1000 which is 30% more than the price tag of an unlocked iPhone sold in USA. Personally I love iPhones as there is no match for the user experience provided by Apple as well as the wide range of really meaning applications available for iPhone. But it breaks heart to spend $1000 for a phone and I’m forced to look at alternates available in the market. Here are the four iPhone 4S alternates available in almost all the countries where we can buy iPhone 4S Google Galaxy Nexus The Galaxy Nexus is Google’s own Android smartphone manufactured by Samsung and sold under the brand name of Google Nexus. Galaxy Nexus is the pure Android phone available in the market without any bloat software or custom user interfaces like other Androids available in the market. Galaxy Nexus is also the first Android phone to be shipped with the latest version of Android OS, Ice Cream Sandwich. This phone is the benchmark for the rest of Android phones that are going to enter the market soon. In the words of Google this smartphone is called as “Galaxy Nexus: Simple. Beautiful. Beyond Smart.”.  BGR review summarizes the phone as This is almost comical at this point, but the Samsung Galaxy Nexus is my favourite Android device in the world. Easily replacing the HTC Rezound, the Motorola DROID RAZR, and Samsung Galaxy S II, the Galaxy Nexus champions in a brand new version of Android that pushes itself further than almost any other mobile OS in the industry. Samsung Galaxy S II The one single company that is able to sell more smartphones than Apple is Samsung. Samsung recently displaced Apple from the top smartphone seller spot and occupied it with loads of pride. Samsung’s Galaxy S II fits as one the best alternatives to Apple’s iPhone 4S with it’s beautiful design and remarkable performance. Engadget summarizes Samsung Galaxy S2 review as It’s the best Android smartphone yet, but more importantly, it might well be the best smartphone, period. Of course, a 4.3-inch screen size won’t suit everyone, no matter how stupendously thin the device that carries it may be, and we also can’t say for sure that the Galaxy S II would justify a long-term iOS user foresaking his investment into one ecosystem and making the leap to another. Nonetheless, if you’re asking us what smartphone to buy today, unconstrained by such externalities, the Galaxy S II would be the clear choice. Sometimes it’s just as simple as that. Nokia Lumia 800 Here comes unexpected Windows Phone in to the boxing ring. May be they are not as great as Androids available in the market today, but they are picking up very quickly. Especially the Nokia Lumia 800 seems to be first ever Windows Phone 7 aimed at competing serious with Androids and iPhones available in the market. There are reports that Nokia Lumia 800 is outselling all Androids in UK and few high profile tech blogs are calling it as the king of Windows Phone. Considering this phone while evaluating the alternative of iPhone 4S will not disappoint you. We assure. Droid RAZR Remember the Motorola Driod that swept entire Android market share couple of years ago? The first two version of Motorola Droids were the best in the market and they out performed almost every other Android phone those days. The invasion of Samsung Androids, Motorola lost it charm. With the recent release of Droid RAZR, Motorola seems to be in the right direction to reclaiming the prestige. Droid RAZR is the thinnest smartphone available in the market and it’s beauty is not just skin deep. Here is a review of the phone from Engadget blog the RAZR’s beauty is not only skin deep. The LTE radio, 1.2GHz dual-core processor and 1GB of RAM make sure this sleek number is ready to run with the big boys. It kept pace with, and in some cases clearly outclassed its high-end competition. Despite its deficiencies in the display department and underwhelming battery life, the RAZR looks to be a perfectly viable alternative when considering the similarly-pricey Rezound and Galaxy Nexus Further Reading So we have seen the four alternates of iPhone 4S available in the market and I personally love to buy a Samsung smartphone if I’m don’t have money to afford an iPhone 4S. If you are interested in deep diving into the alternates, here few links that help you do more research Apple iPhone 4S vs. Samsung Galaxy Nexus vs. Motorola Droid RAZR: How Their Specs Compare by Huffington Post Nokia Lumia 800 vs. iPhone 4S vs. Nexus Galaxy: Spec Smackdown by PC World Browser Speed Test: Nokia Lumia 800 vs. iPhone 4S vs. Samsung Galaxy S II – by Gizmodo iPhone 4S vs Samsung Galaxy S II by pocket lint Apple iPhone 4S vs. Samsung Galaxy S II by techie buzz This article titled,Looking For iPhone 4S Alternatives? Here Are 3 Smartphones You Should Consider, was originally published at Tech Dreams. Grab our rss feed or fan us on Facebook to get updates from us.

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  • How To Switch Back to Outlook 2007 After the 2010 Beta Ends

    - by Matthew Guay
    Are you switching back to Outlook 2007 after trying out Office 2010 beta?  Here’s how you can restore your Outlook data and keep everything working fine after the switch. Whenever you install a newer version of Outlook, it will convert your profile and data files to the latest format.  This makes them work the best in the newer version of Outlook, but may cause problems if you decide to revert to an older version.  If you installed Outlook 2010 beta, it automatically imported and converted your profile from Outlook 2007.  When the beta expires, you will either have to reinstall Office 2007 or purchase a copy of Office 2010. If you choose to reinstall Office 2007, you may notice an error message each time you open Outlook. Outlook will still work fine and all of your data will be saved, but this error message can get annoying.  Here’s how you can create a new profile, import all of your old data, and get rid of this error message. Banish the Error Message with a New Profile To get rid of this error message, we need to create a new Outlook profile.  First, make sure your Outlook data files are backed up.  Your messages, contacts, calendar, and more are stored in a .pst file in your appdata folder.  Enter the following in the address bar of an Explorer window to open your Outlook data folder, and replace username with your user name: C:\Users\username\AppData\Local\Microsoft\Outlook Copy the Outlook Personal Folders (.pst) files that contain your data. Its name is usually your email address, though it may have a different name.  If in doubt, select all of the Outlook Personal Folders files, copy them, and save them in another safe place (such as your Documents folder). Now, let’s remove your old profile.  Open Control Panel, and select Mail.  In Windows Vista or 7, simply enter “Mail” in the search box and select the first entry. Click the “Show Profiles…” button. Now, select your Outlook profile, and click Remove.  This will not delete your data files, but will remove them from Outlook. Press Yes to confirm that you wish to remove this profile. Open Outlook, and you will be asked to create a new profile.  Enter a name for your new profile, and press Ok. Now enter your email account information to setup Outlook as normal. Outlook will attempt to automatically configure your account settings.  This usually works for accounts with popular email systems, but if it fails to find your information you can enter it manually.  Press finish when everything’s done. Outlook will now go ahead and download messages from your email account.  In our test, we used a Gmail account that still had all of our old messages online.  Those files are backed up in our old Outlook data files, so we can save time and not download them.  Click the Send/Receive button on the bottom of the window, and select “Cancel Send/Receive”. Restore Your Old Outlook Data Let’s add our old Outlook file back to Outlook 2007.  Exit Outlook, and then go back to Control Panel, and select Mail as above.  This time, click the Data Files button. Click the Add button on the top left. Select “Office Outlook Personal Folders File (.pst)”, and click Ok. Now, select your old Outlook data file.  It should be in the folder that opens by default; if not, browse to the backup copy we saved earlier, and select it. Press Ok at the next dialog to accept the default settings. Now, select the data file we just imported, and click “Set as Default”. Now, all of your old messages, appointments, contacts, and everything else will be right in Outlook ready for you.  Click Ok, and then open Outlook to see the change. All of the data that was in Outlook 2010 is now ready to use in Outlook 2007.  You won’t have to wait to re-download all of your emails from the server since everything’s still here ready to be used.  And when you open Outlook, you won’t see any error messages, either! Conclusion Migrating your Outlook profile back to Outlook 2007 is fairly easy, and with these steps, you can avoid seeing an error message every time you open Outlook.  With all your data in tact, you’re ready to get back to work instead of getting frustrated with Outlook.  Many of us use webmail and keep all of our messages in the cloud, but even on broadband connections it can take a long time to download several gigabytes of emails. Similar Articles Productive Geek Tips Opening Attachments in Outlook 2007 by KeyboardQuickly Create Appointments from Tasks with Outlook 2007’s To-Do BarFix For Outlook 2007 Constantly Asking for Password on VistaPin Microsoft Outlook to the Desktop BackgroundOur Look at the LinkedIn Social Connector for Outlook TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Download Free MP3s from Amazon Awe inspiring, inter-galactic theme (Win 7) Case Study – How to Optimize Popular Wordpress Sites Restore Hidden Updates in Windows 7 & Vista Iceland an Insurance Job? Find Downloads and Add-ins for Outlook

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  • Where does ASP.NET Web API Fit?

    - by Rick Strahl
    With the pending release of ASP.NET MVC 4 and the new ASP.NET Web API, there has been a lot of discussion of where the new Web API technology fits in the ASP.NET Web stack. There are a lot of choices to build HTTP based applications available now on the stack - we've come a long way from when WebForms and Http Handlers/Modules where the only real options. Today we have WebForms, MVC, ASP.NET Web Pages, ASP.NET AJAX, WCF REST and now Web API as well as the core ASP.NET runtime to choose to build HTTP content with. Web API definitely squarely addresses the 'API' aspect - building consumable services - rather than HTML content, but even to that end there are a lot of choices you have today. So where does Web API fit, and when doesn't it? But before we get into that discussion, let's talk about what a Web API is and why we should care. What's a Web API? HTTP 'APIs' (Microsoft's new terminology for a service I guess)  are becoming increasingly more important with the rise of the many devices in use today. Most mobile devices like phones and tablets run Apps that are using data retrieved from the Web over HTTP. Desktop applications are also moving in this direction with more and more online content and synching moving into even traditional desktop applications. The pending Windows 8 release promises an app like platform for both the desktop and other devices, that also emphasizes consuming data from the Cloud. Likewise many Web browser hosted applications these days are relying on rich client functionality to create and manipulate the browser user interface, using AJAX rather than server generated HTML data to load up the user interface with data. These mobile or rich Web applications use their HTTP connection to return data rather than HTML markup in the form of JSON or XML typically. But an API can also serve other kinds of data, like images or other binary files, or even text data and HTML (although that's less common). A Web API is what feeds rich applications with data. ASP.NET Web API aims to service this particular segment of Web development by providing easy semantics to route and handle incoming requests and an easy to use platform to serve HTTP data in just about any content format you choose to create and serve from the server. But .NET already has various HTTP Platforms The .NET stack already includes a number of technologies that provide the ability to create HTTP service back ends, and it has done so since the very beginnings of the .NET platform. From raw HTTP Handlers and Modules in the core ASP.NET runtime, to high level platforms like ASP.NET MVC, Web Forms, ASP.NET AJAX and the WCF REST engine (which technically is not ASP.NET, but can integrate with it), you've always been able to handle just about any kind of HTTP request and response with ASP.NET. The beauty of the raw ASP.NET platform is that it provides you everything you need to build just about any type of HTTP application you can dream up from low level APIs/custom engines to high level HTML generation engine. ASP.NET as a core platform clearly has stood the test of time 10+ years later and all other frameworks like Web API are built on top of this ASP.NET core. However, although it's possible to create Web APIs / Services using any of the existing out of box .NET technologies, none of them have been a really nice fit for building arbitrary HTTP based APIs. Sure, you can use an HttpHandler to create just about anything, but you have to build a lot of plumbing to build something more complex like a comprehensive API that serves a variety of requests, handles multiple output formats and can easily pass data up to the server in a variety of ways. Likewise you can use ASP.NET MVC to handle routing and creating content in various formats fairly easily, but it doesn't provide a great way to automatically negotiate content types and serve various content formats directly (it's possible to do with some plumbing code of your own but not built in). Prior to Web API, Microsoft's main push for HTTP services has been WCF REST, which was always an awkward technology that had a severe personality conflict, not being clear on whether it wanted to be part of WCF or purely a separate technology. In the end it didn't do either WCF compatibility or WCF agnostic pure HTTP operation very well, which made for a very developer-unfriendly environment. Personally I didn't like any of the implementations at the time, so much so that I ended up building my own HTTP service engine (as part of the West Wind Web Toolkit), as have a few other third party tools that provided much better integration and ease of use. With the release of Web API for the first time I feel that I can finally use the tools in the box and not have to worry about creating and maintaining my own toolkit as Web API addresses just about all the features I implemented on my own and much more. ASP.NET Web API provides a better HTTP Experience ASP.NET Web API differentiates itself from the previous Microsoft in-box HTTP service solutions in that it was built from the ground up around the HTTP protocol and its messaging semantics. Unlike WCF REST or ASP.NET AJAX with ASMX, it’s a brand new platform rather than bolted on technology that is supposed to work in the context of an existing framework. The strength of the new ASP.NET Web API is that it combines the best features of the platforms that came before it, to provide a comprehensive and very usable HTTP platform. Because it's based on ASP.NET and borrows a lot of concepts from ASP.NET MVC, Web API should be immediately familiar and comfortable to most ASP.NET developers. Here are some of the features that Web API provides that I like: Strong Support for URL Routing to produce clean URLs using familiar MVC style routing semantics Content Negotiation based on Accept headers for request and response serialization Support for a host of supported output formats including JSON, XML, ATOM Strong default support for REST semantics but they are optional Easily extensible Formatter support to add new input/output types Deep support for more advanced HTTP features via HttpResponseMessage and HttpRequestMessage classes and strongly typed Enums to describe many HTTP operations Convention based design that drives you into doing the right thing for HTTP Services Very extensible, based on MVC like extensibility model of Formatters and Filters Self-hostable in non-Web applications  Testable using testing concepts similar to MVC Web API is meant to handle any kind of HTTP input and produce output and status codes using the full spectrum of HTTP functionality available in a straight forward and flexible manner. Looking at the list above you can see that a lot of functionality is very similar to ASP.NET MVC, so many ASP.NET developers should feel quite comfortable with the concepts of Web API. The Routing and core infrastructure of Web API are very similar to how MVC works providing many of the benefits of MVC, but with focus on HTTP access and manipulation in Controller methods rather than HTML generation in MVC. There’s much improved support for content negotiation based on HTTP Accept headers with the framework capable of detecting automatically what content the client is sending and requesting and serving the appropriate data format in return. This seems like such a little and obvious thing, but it's really important. Today's service backends often are used by multiple clients/applications and being able to choose the right data format for what fits best for the client is very important. While previous solutions were able to accomplish this using a variety of mixed features of WCF and ASP.NET, Web API combines all this functionality into a single robust server side HTTP framework that intrinsically understands the HTTP semantics and subtly drives you in the right direction for most operations. And when you need to customize or do something that is not built in, there are lots of hooks and overrides for most behaviors, and even many low level hook points that allow you to plug in custom functionality with relatively little effort. No Brainers for Web API There are a few scenarios that are a slam dunk for Web API. If your primary focus of an application or even a part of an application is some sort of API then Web API makes great sense. HTTP ServicesIf you're building a comprehensive HTTP API that is to be consumed over the Web, Web API is a perfect fit. You can isolate the logic in Web API and build your application as a service breaking out the logic into controllers as needed. Because the primary interface is the service there's no confusion of what should go where (MVC or API). Perfect fit. Primary AJAX BackendsIf you're building rich client Web applications that are relying heavily on AJAX callbacks to serve its data, Web API is also a slam dunk. Again because much if not most of the business logic will probably end up in your Web API service logic, there's no confusion over where logic should go and there's no duplication. In Single Page Applications (SPA), typically there's very little HTML based logic served other than bringing up a shell UI and then filling the data from the server with AJAX which means the business logic required for data retrieval and data acceptance and validation too lives in the Web API. Perfect fit. Generic HTTP EndpointsAnother good fit are generic HTTP endpoints that to serve data or handle 'utility' type functionality in typical Web applications. If you need to implement an image server, or an upload handler in the past I'd implement that as an HTTP handler. With Web API you now have a well defined place where you can implement these types of generic 'services' in a location that can easily add endpoints (via Controller methods) or separated out as more full featured APIs. Granted this could be done with MVC as well, but Web API seems a clearer and more well defined place to store generic application services. This is one thing I used to do a lot of in my own libraries and Web API addresses this nicely. Great fit. Mixed HTML and AJAX Applications: Not a clear Choice  For all the commonality that Web API and MVC share they are fundamentally different platforms that are independent of each other. A lot of people have asked when does it make sense to use MVC vs. Web API when you're dealing with typical Web application that creates HTML and also uses AJAX functionality for rich functionality. While it's easy to say that all 'service'/AJAX logic should go into a Web API and all HTML related generation into MVC, that can often result in a lot of code duplication. Also MVC supports JSON and XML result data fairly easily as well so there's some confusion where that 'trigger point' is of when you should switch to Web API vs. just implementing functionality as part of MVC controllers. Ultimately there's a tradeoff between isolation of functionality and duplication. A good rule of thumb I think works is that if a large chunk of the application's functionality serves data Web API is a good choice, but if you have a couple of small AJAX requests to serve data to a grid or autocomplete box it'd be overkill to separate out that logic into a separate Web API controller. Web API does add overhead to your application (it's yet another framework that sits on top of core ASP.NET) so it should be worth it .Keep in mind that MVC can generate HTML and JSON/XML and just about any other content easily and that functionality is not going away, so just because you Web API is there it doesn't mean you have to use it. Web API is not a full replacement for MVC obviously either since there's not the same level of support to feed HTML from Web API controllers (although you can host a RazorEngine easily enough if you really want to go that route) so if you're HTML is part of your API or application in general MVC is still a better choice either alone or in combination with Web API. I suspect (and hope) that in the future Web API's functionality will merge even closer with MVC so that you might even be able to mix functionality of both into single Controllers so that you don't have to make any trade offs, but at the moment that's not the case. Some Issues To think about Web API is similar to MVC but not the Same Although Web API looks a lot like MVC it's not the same and some common functionality of MVC behaves differently in Web API. For example, the way single POST variables are handled is different than MVC and doesn't lend itself particularly well to some AJAX scenarios with POST data. Code Duplication I already touched on this in the Mixed HTML and Web API section, but if you build an MVC application that also exposes a Web API it's quite likely that you end up duplicating a bunch of code and - potentially - infrastructure. You may have to create authentication logic both for an HTML application and for the Web API which might need something different altogether. More often than not though the same logic is used, and there's no easy way to share. If you implement an MVC ActionFilter and you want that same functionality in your Web API you'll end up creating the filter twice. AJAX Data or AJAX HTML On a recent post's comments, David made some really good points regarding the commonality of MVC and Web API's and its place. One comment that caught my eye was a little more generic, regarding data services vs. HTML services. David says: I see a lot of merit in the combination of Knockout.js, client side templates and view models, calling Web API for a responsive UI, but sometimes late at night that still leaves me wondering why I would no longer be using some of the nice tooling and features that have evolved in MVC ;-) You know what - I can totally relate to that. On the last Web based mobile app I worked on, we decided to serve HTML partials to the client via AJAX for many (but not all!) things, rather than sending down raw data to inject into the DOM on the client via templating or direct manipulation. While there are definitely more bytes on the wire, with this, the overhead ended up being actually fairly small if you keep the 'data' requests small and atomic. Performance was often made up by the lack of client side rendering of HTML. Server rendered HTML for AJAX templating gives so much better infrastructure support without having to screw around with 20 mismatched client libraries. Especially with MVC and partials it's pretty easy to break out your HTML logic into very small, atomic chunks, so it's actually easy to create small rendering islands that can be used via composition on the server, or via AJAX calls to small, tight partials that return HTML to the client. Although this is often frowned upon as to 'heavy', it worked really well in terms of developer effort as well as providing surprisingly good performance on devices. There's still plenty of jQuery and AJAX logic happening on the client but it's more manageable in small doses rather than trying to do the entire UI composition with JavaScript and/or 'not-quite-there-yet' template engines that are very difficult to debug. This is not an issue directly related to Web API of course, but something to think about especially for AJAX or SPA style applications. Summary Web API is a great new addition to the ASP.NET platform and it addresses a serious need for consolidation of a lot of half-baked HTTP service API technologies that came before it. Web API feels 'right', and hits the right combination of usability and flexibility at least for me and it's a good fit for true API scenarios. However, just because a new platform is available it doesn't meant that other tools or tech that came before it should be discarded or even upgraded to the new platform. There's nothing wrong with continuing to use MVC controller methods to handle API tasks if that's what your app is running now - there's very little to be gained by upgrading to Web API just because. But going forward Web API clearly is the way to go, when building HTTP data interfaces and it's good to see that Microsoft got this one right - it was sorely needed! Resources ASP.NET Web API AspConf Ask the Experts Session (first 5 minutes) © Rick Strahl, West Wind Technologies, 2005-2012Posted in Web Api   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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  • Our Look at the Internet Explorer 9 Platform Preview

    - by Asian Angel
    Have you been hearing all about Microsoft’s work on Internet Explorer 9 and are curious about it? If you are wanting a taste of the upcoming release then join us as we take a look at the Internet Explorer 9 Platform Preview. Note: Windows Vista and Server 2008 users may need to install a Platform Update (see link at bottom for more information). Getting Started If you are curious about the systems that the platform preview will operate on here is an excerpt from the FAQ page (link provided below). There are two important points of interest here: The platform preview does not replace your regular Internet Explorer installation The platform preview (and the final version of Internet Explorer 9) will not work on Windows XP There really is not a lot to the install process…basically all that you will have to deal with is the “EULA Window” and the “Install Finished Window”. Note: The platform preview will install to a “Program Files Folder” named “Internet Explorer Platform Preview”. Internet Explorer 9 Platform Preview in Action When you start the platform preview up for the first time you will be presented with the Internet Explorer 9 Test Drive homepage. Do not be surprised that there is not a lot to the UI at this time…but you can get a good idea of how Internet Explorer will act. Note: You will not be able to alter the “Homepage” for the platform preview. Of the four menus available there are two that will be of interest to most people…the “Page & Debug Menus”. If you go to navigate to a new webpage you will need to go through the “Page Menu” unless you have installed the Address Bar Mini-Tool (shown below). Want to see what a webpage will look like in an older version of Internet Explorer? Then choose your version in the “Debug Menu”. We did find it humorous that IE6 was excluded from the choices offered. Here is what the URL entry window looks like if you are using the “Page Menu” to navigate between websites. Here is the main page of the site here displayed in “IE9 Mode”…looking good. Here is the main page viewed in “Forced IE5 Document Mode”. There were some minor differences (colors, sidebar, etc.) in how the main page displayed in comparison to “IE9 Mode”. Being able to switch between modes makes for an interesting experience… As you can see there is not much to the “Context Menu” at the moment. Notice the slightly altered icon for the platform preview… “Add” an Address Bar of Sorts If you would like to use a “make-shift” Address Bar with the platform preview you can set up the portable file (IE9browser.exe) for the Internet Explorer 9 Test Platform Addressbar Mini-Tool. Just place it in an appropriate folder, create a shortcut for it, and it will be ready to go. Here is a close look at the left side of the Address Bar Mini-Tool. You can try to access “IE Favorites” but may have sporadic results like those we experienced during our tests. Note: The Address Bar Mini-Tool will not line up perfectly with the platform preview but still makes a nice addition. And a close look at the right side of the Address Bar Mini-Tool. In order to completely shut down the Address Bar Mini-Tool you will need to click on “Close”. Each time that you enter an address into the Address Bar Mini-Tool it will open a new window/instance of the platform preview. Note: During our tests we noticed that clicking on “Home” in the “Page Menu” opened the previously viewed website but once we closed and restarted the platform preview the test drive website was the starting/home page again. Even if the platform preview is not running the Address Bar Mini-Tool can still run as shown here. Note: You will not be able to move the Address Bar Mini-Tool from its’ locked-in position at the top of the screen. Now for some fun. With just the Address Bar Mini-Tool open you can enter an address and cause the platform preview to open. Here is our example from above now open in the platform preview…good to go. Conclusion During our tests we did experience the occasional crash but overall we were pleased with the platform preview’s performance. The platform preview handled rather well and definitely seemed much quicker than Internet Explorer 8 on our test system (a definite bonus!). If you are an early adopter then this could certainly get you in the mood for the upcoming beta releases! Links Download the Internet Explorer 9 Preview Platform Download the Internet Explorer 9 Test Platform Addressbar Mini-Tool Information about Platform Update for Windows Vista & Server 2008 View the Internet Explorer 9 Platform Preview FAQ Similar Articles Productive Geek Tips Mysticgeek Blog: A Look at Internet Explorer 8 Beta 1 on Windows XPMake Ctrl+Tab in Internet Explorer 7 Use Most Recent OrderRemove ISP Text or Corporate Branding from Internet Explorer Title BarWhy Can’t I Turn the Details/Preview Panes On or Off in Windows Vista Explorer?Prevent Firefox or Internet Explorer from Printing the URL on Every Page TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Awesome Lyrics Finder for Winamp & Windows Media Player Download Videos from Hulu Pixels invade Manhattan Convert PDF files to ePub to read on your iPad Hide Your Confidential Files Inside Images Get Wildlife Photography Tips at BBC’s PhotoMasterClasses

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  • VS 2010 SP1 and SQL CE

    - by ScottGu
    Last month we released the Beta of VS 2010 Service Pack 1 (SP1).  You can learn more about the VS 2010 SP1 Beta from Jason Zander’s two blog posts about it, and from Scott Hanselman’s blog post that covers some of the new capabilities enabled with it.   You can download and install the VS 2010 SP1 Beta here. Last week I blogged about the new Visual Studio support for IIS Express that we are adding with VS 2010 SP1. In today’s post I’m going to talk about the new VS 2010 SP1 tooling support for SQL CE, and walkthrough some of the cool scenarios it enables.  SQL CE – What is it and why should you care? SQL CE is a free, embedded, database engine that enables easy database storage. No Database Installation Required SQL CE does not require you to run a setup or install a database server in order to use it.  You can simply copy the SQL CE binaries into the \bin directory of your ASP.NET application, and then your web application can use it as a database engine.  No setup or extra security permissions are required for it to run. You do not need to have an administrator account on the machine. Just copy your web application onto any server and it will work. This is true even of medium-trust applications running in a web hosting environment. SQL CE runs in-memory within your ASP.NET application and will start-up when you first access a SQL CE database, and will automatically shutdown when your application is unloaded.  SQL CE databases are stored as files that live within the \App_Data folder of your ASP.NET Applications. Works with Existing Data APIs SQL CE 4 works with existing .NET-based data APIs, and supports a SQL Server compatible query syntax.  This means you can use existing data APIs like ADO.NET, as well as use higher-level ORMs like Entity Framework and NHibernate with SQL CE.  This enables you to use the same data programming skills and data APIs you know today. Supports Development, Testing and Production Scenarios SQL CE can be used for development scenarios, testing scenarios, and light production usage scenarios.  With the SQL CE 4 release we’ve done the engineering work to ensure that SQL CE won’t crash or deadlock when used in a multi-threaded server scenario (like ASP.NET).  This is a big change from previous releases of SQL CE – which were designed for client-only scenarios and which explicitly blocked running in web-server environments.  Starting with SQL CE 4 you can use it in a web-server as well. There are no license restrictions with SQL CE.  It is also totally free. Easy Migration to SQL Server SQL CE is an embedded database – which makes it ideal for development, testing, and light-usage scenarios.  For high-volume sites and applications you’ll probably want to migrate your database to use SQL Server Express (which is free), SQL Server or SQL Azure.  These servers enable much better scalability, more development features (including features like Stored Procedures – which aren’t supported with SQL CE), as well as more advanced data management capabilities. We’ll ship migration tools that enable you to optionally take SQL CE databases and easily upgrade them to use SQL Server Express, SQL Server, or SQL Azure.  You will not need to change your code when upgrading a SQL CE database to SQL Server or SQL Azure.  Our goal is to enable you to be able to simply change the database connection string in your web.config file and have your application just work. New Tooling Support for SQL CE in VS 2010 SP1 VS 2010 SP1 includes much improved tooling support for SQL CE, and adds support for using SQL CE within ASP.NET projects for the first time.  With VS 2010 SP1 you can now: Create new SQL CE Databases Edit and Modify SQL CE Database Schema and Indexes Populate SQL CE Databases within Data Use the Entity Framework (EF) designer to create model layers against SQL CE databases Use EF Code First to define model layers in code, then create a SQL CE database from them, and optionally edit the DB with VS Deploy SQL CE databases to remote servers using Web Deploy and optionally convert them to full SQL Server databases You can take advantage of all of the above features from within both ASP.NET Web Forms and ASP.NET MVC based projects. Download You can enable SQL CE tooling support within VS 2010 by first installing VS 2010 SP1 (beta). Once SP1 is installed, you’ll also then need to install the SQL CE Tools for Visual Studio download.  This is a separate download that enables the SQL CE tooling support for VS 2010 SP1. Walkthrough of Two Scenarios In this blog post I’m going to walkthrough how you can take advantage of SQL CE and VS 2010 SP1 using both an ASP.NET Web Forms and an ASP.NET MVC based application. Specifically, we’ll walkthrough: How to create a SQL CE database using VS 2010 SP1, then use the EF4 visual designers in Visual Studio to construct a model layer from it, and then display and edit the data using an ASP.NET GridView control. How to use an EF Code First approach to define a model layer using POCO classes and then have EF Code-First “auto-create” a SQL CE database for us based on our model classes.  We’ll then look at how we can use the new VS 2010 SP1 support for SQL CE to inspect the database that was created, populate it with data, and later make schema changes to it.  We’ll do all this within the context of an ASP.NET MVC based application. You can follow the two walkthroughs below on your own machine by installing VS 2010 SP1 (beta) and then installing the SQL CE Tools for Visual Studio download (which is a separate download that enables SQL CE tooling support for VS 2010 SP1). Walkthrough 1: Create a SQL CE Database, Create EF Model Classes, Edit the Data with a GridView This first walkthrough will demonstrate how to create and define a SQL CE database within an ASP.NET Web Form application.  We’ll then build an EF model layer for it and use that model layer to enable data editing scenarios with an <asp:GridView> control. Step 1: Create a new ASP.NET Web Forms Project We’ll begin by using the File->New Project menu command within Visual Studio to create a new ASP.NET Web Forms project.  We’ll use the “ASP.NET Web Application” project template option so that it has a default UI skin implemented: Step 2: Create a SQL CE Database Right click on the “App_Data” folder within the created project and choose the “Add->New Item” menu command: This will bring up the “Add Item” dialog box.  Select the “SQL Server Compact 4.0 Local Database” item (new in VS 2010 SP1) and name the database file to create “Store.sdf”: Note that SQL CE database files have a .sdf filename extension. Place them within the /App_Data folder of your ASP.NET application to enable easy deployment. When we clicked the “Add” button above a Store.sdf file was added to our project: Step 3: Adding a “Products” Table Double-clicking the “Store.sdf” database file will open it up within the Server Explorer tab.  Since it is a new database there are no tables within it: Right click on the “Tables” icon and choose the “Create Table” menu command to create a new database table.  We’ll name the new table “Products” and add 4 columns to it.  We’ll mark the first column as a primary key (and make it an identify column so that its value will automatically increment with each new row): When we click “ok” our new Products table will be created in the SQL CE database. Step 4: Populate with Data Once our Products table is created it will show up within the Server Explorer.  We can right-click it and choose the “Show Table Data” menu command to edit its data: Let’s add a few sample rows of data to it: Step 5: Create an EF Model Layer We have a SQL CE database with some data in it – let’s now create an EF Model Layer that will provide a way for us to easily query and update data within it. Let’s right-click on our project and choose the “Add->New Item” menu command.  This will bring up the “Add New Item” dialog – select the “ADO.NET Entity Data Model” item within it and name it “Store.edmx” This will add a new Store.edmx item to our solution explorer and launch a wizard that allows us to quickly create an EF model: Select the “Generate From Database” option above and click next.  Choose to use the Store.sdf SQL CE database we just created and then click next again.  The wizard will then ask you what database objects you want to import into your model.  Let’s choose to import the “Products” table we created earlier: When we click the “Finish” button Visual Studio will open up the EF designer.  It will have a Product entity already on it that maps to the “Products” table within our SQL CE database: The VS 2010 SP1 EF designer works exactly the same with SQL CE as it does already with SQL Server and SQL Express.  The Product entity above will be persisted as a class (called “Product”) that we can programmatically work against within our ASP.NET application. Step 6: Compile the Project Before using your model layer you’ll need to build your project.  Do a Ctrl+Shift+B to compile the project, or use the Build->Build Solution menu command. Step 7: Create a Page that Uses our EF Model Layer Let’s now create a simple ASP.NET Web Form that contains a GridView control that we can use to display and edit the our Products data (via the EF Model Layer we just created). Right-click on the project and choose the Add->New Item command.  Select the “Web Form from Master Page” item template, and name the page you create “Products.aspx”.  Base the master page on the “Site.Master” template that is in the root of the project. Add an <h2>Products</h2> heading the new Page, and add an <asp:gridview> control within it: Then click the “Design” tab to switch into design-view. Select the GridView control, and then click the top-right corner to display the GridView’s “Smart Tasks” UI: Choose the “New data source…” drop down option above.  This will bring up the below dialog which allows you to pick your Data Source type: Select the “Entity” data source option – which will allow us to easily connect our GridView to the EF model layer we created earlier.  This will bring up another dialog that allows us to pick our model layer: Select the “StoreEntities” option in the dropdown – which is the EF model layer we created earlier.  Then click next – which will allow us to pick which entity within it we want to bind to: Select the “Products” entity in the above dialog – which indicates that we want to bind against the “Product” entity class we defined earlier.  Then click the “Enable automatic updates” checkbox to ensure that we can both query and update Products.  When you click “Finish” VS will wire-up an <asp:EntityDataSource> to your <asp:GridView> control: The last two steps we’ll do will be to click the “Enable Editing” checkbox on the Grid (which will cause the Grid to display an “Edit” link on each row) and (optionally) use the Auto Format dialog to pick a UI template for the Grid. Step 8: Run the Application Let’s now run our application and browse to the /Products.aspx page that contains our GridView.  When we do so we’ll see a Grid UI of the Products within our SQL CE database. Clicking the “Edit” link for any of the rows will allow us to edit their values: When we click “Update” the GridView will post back the values, persist them through our EF Model Layer, and ultimately save them within our SQL CE database. Learn More about using EF with ASP.NET Web Forms Read this tutorial series on the http://asp.net site to learn more about how to use EF with ASP.NET Web Forms.  The tutorial series uses SQL Express as the database – but the nice thing is that all of the same steps/concepts can also now also be done with SQL CE.   Walkthrough 2: Using EF Code-First with SQL CE and ASP.NET MVC 3 We used a database-first approach with the sample above – where we first created the database, and then used the EF designer to create model classes from the database.  In addition to supporting a designer-based development workflow, EF also enables a more code-centric option which we call “code first development”.  Code-First Development enables a pretty sweet development workflow.  It enables you to: Define your model objects by simply writing “plain old classes” with no base classes or visual designer required Use a “convention over configuration” approach that enables database persistence without explicitly configuring anything Optionally override the convention-based persistence and use a fluent code API to fully customize the persistence mapping Optionally auto-create a database based on the model classes you define – allowing you to start from code first I’ve done several blog posts about EF Code First in the past – I really think it is great.  The good news is that it also works very well with SQL CE. The combination of SQL CE, EF Code First, and the new VS tooling support for SQL CE, enables a pretty nice workflow.  Below is a simple example of how you can use them to build a simple ASP.NET MVC 3 application. Step 1: Create a new ASP.NET MVC 3 Project We’ll begin by using the File->New Project menu command within Visual Studio to create a new ASP.NET MVC 3 project.  We’ll use the “Internet Project” template so that it has a default UI skin implemented: Step 2: Use NuGet to Install EFCodeFirst Next we’ll use the NuGet package manager (automatically installed by ASP.NET MVC 3) to add the EFCodeFirst library to our project.  We’ll use the Package Manager command shell to do this.  Bring up the package manager console within Visual Studio by selecting the View->Other Windows->Package Manager Console menu command.  Then type: install-package EFCodeFirst within the package manager console to download the EFCodeFirst library and have it be added to our project: When we enter the above command, the EFCodeFirst library will be downloaded and added to our application: Step 3: Build Some Model Classes Using a “code first” based development workflow, we will create our model classes first (even before we have a database).  We create these model classes by writing code. For this sample, we will right click on the “Models” folder of our project and add the below three classes to our project: The “Dinner” and “RSVP” model classes above are “plain old CLR objects” (aka POCO).  They do not need to derive from any base classes or implement any interfaces, and the properties they expose are standard .NET data-types.  No data persistence attributes or data code has been added to them.   The “NerdDinners” class derives from the DbContext class (which is supplied by EFCodeFirst) and handles the retrieval/persistence of our Dinner and RSVP instances from a database. Step 4: Listing Dinners We’ve written all of the code necessary to implement our model layer for this simple project.  Let’s now expose and implement the URL: /Dinners/Upcoming within our project.  We’ll use it to list upcoming dinners that happen in the future. We’ll do this by right-clicking on our “Controllers” folder and select the “Add->Controller” menu command.  We’ll name the Controller we want to create “DinnersController”.  We’ll then implement an “Upcoming” action method within it that lists upcoming dinners using our model layer above.  We will use a LINQ query to retrieve the data and pass it to a View to render with the code below: We’ll then right-click within our Upcoming method and choose the “Add-View” menu command to create an “Upcoming” view template that displays our dinners.  We’ll use the “empty” template option within the “Add View” dialog and write the below view template using Razor: Step 4: Configure our Project to use a SQL CE Database We have finished writing all of our code – our last step will be to configure a database connection-string to use. We will point our NerdDinners model class to a SQL CE database by adding the below <connectionString> to the web.config file at the top of our project: EF Code First uses a default convention where context classes will look for a connection-string that matches the DbContext class name.  Because we created a “NerdDinners” class earlier, we’ve also named our connectionstring “NerdDinners”.  Above we are configuring our connection-string to use SQL CE as the database, and telling it that our SQL CE database file will live within the \App_Data directory of our ASP.NET project. Step 5: Running our Application Now that we’ve built our application, let’s run it! We’ll browse to the /Dinners/Upcoming URL – doing so will display an empty list of upcoming dinners: You might ask – but where did it query to get the dinners from? We didn’t explicitly create a database?!? One of the cool features that EF Code-First supports is the ability to automatically create a database (based on the schema of our model classes) when the database we point it at doesn’t exist.  Above we configured  EF Code-First to point at a SQL CE database in the \App_Data\ directory of our project.  When we ran our application, EF Code-First saw that the SQL CE database didn’t exist and automatically created it for us. Step 6: Using VS 2010 SP1 to Explore our newly created SQL CE Database Click the “Show all Files” icon within the Solution Explorer and you’ll see the “NerdDinners.sdf” SQL CE database file that was automatically created for us by EF code-first within the \App_Data\ folder: We can optionally right-click on the file and “Include in Project" to add it to our solution: We can also double-click the file (regardless of whether it is added to the project) and VS 2010 SP1 will open it as a database we can edit within the “Server Explorer” tab of the IDE. Below is the view we get when we double-click our NerdDinners.sdf SQL CE file.  We can drill in to see the schema of the Dinners and RSVPs tables in the tree explorer.  Notice how two tables - Dinners and RSVPs – were automatically created for us within our SQL CE database.  This was done by EF Code First when we accessed the NerdDinners class by running our application above: We can right-click on a Table and use the “Show Table Data” command to enter some upcoming dinners in our database: We’ll use the built-in editor that VS 2010 SP1 supports to populate our table data below: And now when we hit “refresh” on the /Dinners/Upcoming URL within our browser we’ll see some upcoming dinners show up: Step 7: Changing our Model and Database Schema Let’s now modify the schema of our model layer and database, and walkthrough one way that the new VS 2010 SP1 Tooling support for SQL CE can make this easier.  With EF Code-First you typically start making database changes by modifying the model classes.  For example, let’s add an additional string property called “UrlLink” to our “Dinner” class.  We’ll use this to point to a link for more information about the event: Now when we re-run our project, and visit the /Dinners/Upcoming URL we’ll see an error thrown: We are seeing this error because EF Code-First automatically created our database, and by default when it does this it adds a table that helps tracks whether the schema of our database is in sync with our model classes.  EF Code-First helpfully throws an error when they become out of sync – making it easier to track down issues at development time that you might otherwise only find (via obscure errors) at runtime.  Note that if you do not want this feature you can turn it off by changing the default conventions of your DbContext class (in this case our NerdDinners class) to not track the schema version. Our model classes and database schema are out of sync in the above example – so how do we fix this?  There are two approaches you can use today: Delete the database and have EF Code First automatically re-create the database based on the new model class schema (losing the data within the existing DB) Modify the schema of the existing database to make it in sync with the model classes (keeping/migrating the data within the existing DB) There are a couple of ways you can do the second approach above.  Below I’m going to show how you can take advantage of the new VS 2010 SP1 Tooling support for SQL CE to use a database schema tool to modify our database structure.  We are also going to be supporting a “migrations” feature with EF in the future that will allow you to automate/script database schema migrations programmatically. Step 8: Modify our SQL CE Database Schema using VS 2010 SP1 The new SQL CE Tooling support within VS 2010 SP1 makes it easy to modify the schema of our existing SQL CE database.  To do this we’ll right-click on our “Dinners” table and choose the “Edit Table Schema” command: This will bring up the below “Edit Table” dialog.  We can rename, change or delete any of the existing columns in our table, or click at the bottom of the column listing and type to add a new column.  Below I’ve added a new “UrlLink” column of type “nvarchar” (since our property is a string): When we click ok our database will be updated to have the new column and our schema will now match our model classes. Because we are manually modifying our database schema, there is one additional step we need to take to let EF Code-First know that the database schema is in sync with our model classes.  As i mentioned earlier, when a database is automatically created by EF Code-First it adds a “EdmMetadata” table to the database to track schema versions (and hash our model classes against them to detect mismatches between our model classes and the database schema): Since we are manually updating and maintaining our database schema, we don’t need this table – and can just delete it: This will leave us with just the two tables that correspond to our model classes: And now when we re-run our /Dinners/Upcoming URL it will display the dinners correctly: One last touch we could do would be to update our view to check for the new UrlLink property and render a <a> link to it if an event has one: And now when we refresh our /Dinners/Upcoming we will see hyperlinks for the events that have a UrlLink stored in the database: Summary SQL CE provides a free, embedded, database engine that you can use to easily enable database storage.  With SQL CE 4 you can now take advantage of it within ASP.NET projects and applications (both Web Forms and MVC). VS 2010 SP1 provides tooling support that enables you to easily create, edit and modify SQL CE databases – as well as use the standard EF designer against them.  This allows you to re-use your existing skills and data knowledge while taking advantage of an embedded database option.  This is useful both for small applications (where you don’t need the scalability of a full SQL Server), as well as for development and testing scenarios – where you want to be able to rapidly develop/test your application without having a full database instance.  SQL CE makes it easy to later migrate your data to a full SQL Server or SQL Azure instance if you want to – without having to change any code in your application.  All we would need to change in the above two scenarios is the <connectionString> value within the web.config file in order to have our code run against a full SQL Server.  This provides the flexibility to scale up your application starting from a small embedded database solution as needed. Hope this helps, Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

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  • Geek Fun: Virtualized Old School Windows – Windows 95

    - by Matthew Guay
    Last week we enjoyed looking at Windows 3.1 running in VMware Player on Windows 7.  Today, let’s upgrade our 3.1 to 95, and get a look at how most of us remember Windows from the 90’s. In this demo, we’re running the first release of Windows 95 (version 4.00.950) in VMware Player 3.0 running on Windows 7 x64.  For fun, we ran the 95 upgrade on the 3.1 virtual machine we built last week. Windows 95 So let’s get started.  Here’s the first setup screen.  For the record, Windows 95 installed in about 15 minutes or less in VMware in our test. Strangely, Windows 95 offered several installation choices.  They actually let you choose what extra parts of Windows to install if you wished.  Oh, and who wants to run Windows 95 on your “Portable Computer”?  Most smartphones today are more powerful than the “portable computers” of 95. Your productivity may vastly increase if you run Windows 95.  Anyone want to switch? No, I don’t want to restart … I want to use my computer! Welcome to Windows 95!  Hey, did you know you can launch programs from the Start button? Our quick spin around Windows 95 reminded us why Windows got such a bad reputation in the ‘90’s for being unstable.  We didn’t even get our test copy fully booted after installation before we saw our first error screen.  Windows in space … was that the most popular screensaver in Windows 95, or was it just me? Hello Windows 3.1!  The UI was still outdated in some spots.   Ah, yes, Media Player before it got 101 features to compete with iTunes. But, you couldn’t even play CDs in Media Player.  Actually, CD player was one program I used almost daily in Windows 95 back in the day. Want some new programs?  This help file about new programs designed for Windows 95 lists a lot of outdated names in tech.    And, you really may want some programs.  The first edition of Windows 95 didn’t even ship with Internet Explorer.   We’ve still got Minesweeper, though! My Computer had really limited functionality, and by default opened everything in a new window.  Double click on C:, and it opens in a new window.  Ugh. But Explorer is a bit more like more modern versions. Hey, look, Start menu search!  If only it found the files you were looking for… Now I’m feeling old … this shutdown screen brought back so many memories … of shutdowns that wouldn’t shut down! But, you still have to turn off your computer.  I wonder how many old monitors had these words burned into them? So there’s yet another trip down Windows memory lane.  Most of us can remember using Windows 95, so let us know your favorite (or worst) memory of it!  At least we can all be thankful for our modern computers and operating systems today, right?  Similar Articles Productive Geek Tips Geek Fun: Remember the Old-School SkiFree Game?Geek Fun: Virtualized old school Windows 3.11Stupid Geek Tricks: Tile or Cascade Multiple Windows in Windows 7Stupid Geek Tricks: Select Multiple Windows on the TaskbarHow to Delete a System File in Windows 7 or Vista TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Enable Check Box Selection in Windows 7 OnlineOCR – Free OCR Service Betting on the Blind Side, a Vanity Fair article 30 Minimal Logo Designs that Say More with Less LEGO Digital Designer – Free Create a Personal Website Quickly using Flavors.me

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  • Geek Fun: Virtualized Old School Windows – Windows 95

    - by Matthew Guay
    Last week we enjoyed looking at Windows 3.1 running in VMware Player on Windows 7.  Today, let’s upgrade our 3.1 to 95, and get a look at how most of us remember Windows from the 90’s. In this demo, we’re running the first release of Windows 95 (version 4.00.950) in VMware Player 3.0 running on Windows 7 x64.  For fun, we ran the 95 upgrade on the 3.1 virtual machine we built last week. Windows 95 So let’s get started.  Here’s the first setup screen.  For the record, Windows 95 installed in about 15 minutes or less in VMware in our test. Strangely, Windows 95 offered several installation choices.  They actually let you choose what extra parts of Windows to install if you wished.  Oh, and who wants to run Windows 95 on your “Portable Computer”?  Most smartphones today are more powerful than the “portable computers” of 95. Your productivity may vastly increase if you run Windows 95.  Anyone want to switch? No, I don’t want to restart … I want to use my computer! Welcome to Windows 95!  Hey, did you know you can launch programs from the Start button? Our quick spin around Windows 95 reminded us why Windows got such a bad reputation in the ‘90’s for being unstable.  We didn’t even get our test copy fully booted after installation before we saw our first error screen.  Windows in space … was that the most popular screensaver in Windows 95, or was it just me? Hello Windows 3.1!  The UI was still outdated in some spots.   Ah, yes, Media Player before it got 101 features to compete with iTunes. But, you couldn’t even play CDs in Media Player.  Actually, CD player was one program I used almost daily in Windows 95 back in the day. Want some new programs?  This help file about new programs designed for Windows 95 lists a lot of outdated names in tech.    And, you really may want some programs.  The first edition of Windows 95 didn’t even ship with Internet Explorer.   We’ve still got Minesweeper, though! My Computer had really limited functionality, and by default opened everything in a new window.  Double click on C:, and it opens in a new window.  Ugh. But Explorer is a bit more like more modern versions. Hey, look, Start menu search!  If only it found the files you were looking for… Now I’m feeling old … this shutdown screen brought back so many memories … of shutdowns that wouldn’t shut down! But, you still have to turn off your computer.  I wonder how many old monitors had these words burned into them? So there’s yet another trip down Windows memory lane.  Most of us can remember using Windows 95, so let us know your favorite (or worst) memory of it!  At least we can all be thankful for our modern computers and operating systems today, right?  Similar Articles Productive Geek Tips Geek Fun: Remember the Old-School SkiFree Game?Geek Fun: Virtualized old school Windows 3.11Stupid Geek Tricks: Tile or Cascade Multiple Windows in Windows 7Stupid Geek Tricks: Select Multiple Windows on the TaskbarHow to Delete a System File in Windows 7 or Vista TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Enable Check Box Selection in Windows 7 OnlineOCR – Free OCR Service Betting on the Blind Side, a Vanity Fair article 30 Minimal Logo Designs that Say More with Less LEGO Digital Designer – Free Create a Personal Website Quickly using Flavors.me

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  • Remove Office 2010 Beta and Reinstall Office 2007

    - by Matthew Guay
    Have you tried out the Office 2010 beta, but want to go back to Office 2007?  Here’s a step-by-step tutorial on how to remove your Office 2010 beta and reinstall your Office 2007. The Office 2010 beta will expire on October 31, 2010, at which time you may see a dialog like the one below.  At that time, you will need to either upgrade to the final release of Office 2010, or reinstall your previous version of Office. Our computer was running the Office 2010 Home and Business Click to Run beta, and after uninstalling it we reinstalled Office 2007 Home and Student.  This was a Windows Vista computer, but the process will be exactly the same on Windows XP, Vista, or Windows 7.  Additionally, the process to reinstall Office 2007 will be exactly the same regardless of the edition of Office 2007 you’re using. However, please note that if you are running a different edition of Office 2010, especially the 64 bit version, the process may be slightly different.  We will cover this scenario in another article. Remove Office 2010 Click to Run Beta: To remove Office 2010 Click to Run Beta, open Control Panel and select Uninstall a Program. If your computer is running Windows 7, enter “Uninstall a program” in your Start menu search. Scroll down, select “Microsoft Office Click-to-Run 2010 (Beta)”, and click the Uninstall button on the toolbar.  Note that there will be two entries for Office, so make sure to select the “Click-to-Run” entry. This will automatically remove all of Office 2010 and its components.  Click Yes to confirm you want to remove it. Office 2010 beta uninstalled fairly quickly, and a reboot will be required.  Once your computer is rebooted, Office 2010 will be entirely removed. Reinstall Office 2007 Now, you’re to the easy part.  Simply insert your Office 2007 CD, and it should automatically startup the setup.  If not, open Computer and double-click on your CD drive.   Now, double-click on setup.exe to start the installation. Enter your product key, and click Continue…   Click Install Now, or click Customize if you want to change the default installation settings. Wait while Office 2007 installs…it takes around 15 to 20 minutes in our experience.  Once it’s finished  close the installer. Now, open one of the Office applications.  A popup will open asking you to activate Office.  Make sure you’re connected to the internet, and click next; otherwise, you can select to activate over the phone if you do not have internet access. This should only take a minute, and Office 2007 will be activated and ready to run. Everything should work just as it did before you installed Office 2010.  Enjoy! Office Updates Make sure to install the latest updates for Office 2007, as these are not included in your disk.  Check Windows Update (search for Windows Update in the Start menu search), and install all of the available updates for Office 2007, including Service Pack 2. Conclusion This is a great way to keep using Office even if you don’t decide to purchase Office 2010 after it is released.  Additionally, if you’re were using another version of Office, such as Office 2003, then reinstall it as normal after following the steps to remove Office 2010. Similar Articles Productive Geek Tips Add or Remove Apps from the Microsoft Office 2007 or 2010 SuiteDetect and Repair Applications In Microsoft Office 2007Save and Restore Your Microsoft Office SettingsDisable Office 2010 Beta Send-a-Smile from StartupHow to See the About Dialog and Version Information in Office 2007 TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 If Web Browsers Were Modes of Transportation Google Translate (for animals) Out of 100 Tweeters Roadkill’s Scan Port scans for open ports Out of band Security Update for Internet Explorer 7 Cool Looking Screensavers for Windows

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  • Agile Development

    - by James Oloo Onyango
    Alot of literature has and is being written about agile developement and its surrounding philosophies. In my quest to find the best way to express the importance of agile methodologies, i have found Robert C. Martin's "A Satire Of Two Companies" to be both the most concise and thorough! Enjoy the read! Rufus Inc Project Kick Off Your name is Bob. The date is January 3, 2001, and your head still aches from the recent millennial revelry. You are sitting in a conference room with several managers and a group of your peers. You are a project team leader. Your boss is there, and he has brought along all of his team leaders. His boss called the meeting. "We have a new project to develop," says your boss's boss. Call him BB. The points in his hair are so long that they scrape the ceiling. Your boss's points are just starting to grow, but he eagerly awaits the day when he can leave Brylcream stains on the acoustic tiles. BB describes the essence of the new market they have identified and the product they want to develop to exploit this market. "We must have this new project up and working by fourth quarter October 1," BB demands. "Nothing is of higher priority, so we are cancelling your current project." The reaction in the room is stunned silence. Months of work are simply going to be thrown away. Slowly, a murmur of objection begins to circulate around the conference table.   His points give off an evil green glow as BB meets the eyes of everyone in the room. One by one, that insidious stare reduces each attendee to quivering lumps of protoplasm. It is clear that he will brook no discussion on this matter. Once silence has been restored, BB says, "We need to begin immediately. How long will it take you to do the analysis?" You raise your hand. Your boss tries to stop you, but his spitwad misses you and you are unaware of his efforts.   "Sir, we can't tell you how long the analysis will take until we have some requirements." "The requirements document won't be ready for 3 or 4 weeks," BB says, his points vibrating with frustration. "So, pretend that you have the requirements in front of you now. How long will you require for analysis?" No one breathes. Everyone looks around to see whether anyone has some idea. "If analysis goes beyond April 1, we have a problem. Can you finish the analysis by then?" Your boss visibly gathers his courage: "We'll find a way, sir!" His points grow 3 mm, and your headache increases by two Tylenol. "Good." BB smiles. "Now, how long will it take to do the design?" "Sir," you say. Your boss visibly pales. He is clearly worried that his 3 mms are at risk. "Without an analysis, it will not be possible to tell you how long design will take." BB's expression shifts beyond austere.   "PRETEND you have the analysis already!" he says, while fixing you with his vacant, beady little eyes. "How long will it take you to do the design?" Two Tylenol are not going to cut it. Your boss, in a desperate attempt to save his new growth, babbles: "Well, sir, with only six months left to complete the project, design had better take no longer than 3 months."   "I'm glad you agree, Smithers!" BB says, beaming. Your boss relaxes. He knows his points are secure. After a while, he starts lightly humming the Brylcream jingle. BB continues, "So, analysis will be complete by April 1, design will be complete by July 1, and that gives you 3 months to implement the project. This meeting is an example of how well our new consensus and empowerment policies are working. Now, get out there and start working. I'll expect to see TQM plans and QIT assignments on my desk by next week. Oh, and don't forget that your crossfunctional team meetings and reports will be needed for next month's quality audit." "Forget the Tylenol," you think to yourself as you return to your cubicle. "I need bourbon."   Visibly excited, your boss comes over to you and says, "Gosh, what a great meeting. I think we're really going to do some world shaking with this project." You nod in agreement, too disgusted to do anything else. "Oh," your boss continues, "I almost forgot." He hands you a 30-page document. "Remember that the SEI is coming to do an evaluation next week. This is the evaluation guide. You need to read through it, memorize it, and then shred it. It tells you how to answer any questions that the SEI auditors ask you. It also tells you what parts of the building you are allowed to take them to and what parts to avoid. We are determined to be a CMM level 3 organization by June!"   You and your peers start working on the analysis of the new project. This is difficult because you have no requirements. But from the 10-minute introduction given by BB on that fateful morning, you have some idea of what the product is supposed to do.   Corporate process demands that you begin by creating a use case document. You and your team begin enumerating use cases and drawing oval and stick diagrams. Philosophical debates break out among the team members. There is disagreement as to whether certain use cases should be connected with <<extends>> or <<includes>> relationships. Competing models are created, but nobody knows how to evaluate them. The debate continues, effectively paralyzing progress.   After a week, somebody finds the iceberg.com Web site, which recommends disposing entirely of <<extends>> and <<includes>> and replacing them with <<precedes>> and <<uses>>. The documents on this Web site, authored by Don Sengroiux, describes a method known as stalwart-analysis, which claims to be a step-by-step method for translating use cases into design diagrams. More competing use case models are created using this new scheme, but again, people can't agree on how to evaluate them. The thrashing continues. More and more, the use case meetings are driven by emotion rather than by reason. If it weren't for the fact that you don't have requirements, you'd be pretty upset by the lack of progress you are making. The requirements document arrives on February 15. And then again on February 20, 25, and every week thereafter. Each new version contradicts the previous one. Clearly, the marketing folks who are writing the requirements, empowered though they might be, are not finding consensus.   At the same time, several new competing use case templates have been proposed by the various team members. Each template presents its own particularly creative way of delaying progress. The debates rage on. On March 1, Prudence Putrigence, the process proctor, succeeds in integrating all the competing use case forms and templates into a single, all-encompassing form. Just the blank form is 15 pages long. She has managed to include every field that appeared on all the competing templates. She also presents a 159- page document describing how to fill out the use case form. All current use cases must be rewritten according to the new standard.   You marvel to yourself that it now requires 15 pages of fill-in-the-blank and essay questions to answer the question: What should the system do when the user presses Return? The corporate process (authored by L. E. Ott, famed author of "Holistic Analysis: A Progressive Dialectic for Software Engineers") insists that you discover all primary use cases, 87 percent of all secondary use cases, and 36.274 percent of all tertiary use cases before you can complete analysis and enter the design phase. You have no idea what a tertiary use case is. So in an attempt to meet this requirement, you try to get your use case document reviewed by the marketing department, which you hope will know what a tertiary use case is.   Unfortunately, the marketing folks are too busy with sales support to talk to you. Indeed, since the project started, you have not been able to get a single meeting with marketing, which has provided a never-ending stream of changing and contradictory requirements documents.   While one team has been spinning endlessly on the use case document, another team has been working out the domain model. Endless variations of UML documents are pouring out of this team. Every week, the model is reworked.   The team members can't decide whether to use <<interfaces>> or <<types>> in the model. A huge disagreement has been raging on the proper syntax and application of OCL. Others on the team just got back from a 5-day class on catabolism, and have been producing incredibly detailed and arcane diagrams that nobody else can fathom.   On March 27, with one week to go before analysis is to be complete, you have produced a sea of documents and diagrams but are no closer to a cogent analysis of the problem than you were on January 3. **** And then, a miracle happens.   **** On Saturday, April 1, you check your e-mail from home. You see a memo from your boss to BB. It states unequivocally that you are done with the analysis! You phone your boss and complain. "How could you have told BB that we were done with the analysis?" "Have you looked at a calendar lately?" he responds. "It's April 1!" The irony of that date does not escape you. "But we have so much more to think about. So much more to analyze! We haven't even decided whether to use <<extends>> or <<precedes>>!" "Where is your evidence that you are not done?" inquires your boss, impatiently. "Whaaa . . . ." But he cuts you off. "Analysis can go on forever; it has to be stopped at some point. And since this is the date it was scheduled to stop, it has been stopped. Now, on Monday, I want you to gather up all existing analysis materials and put them into a public folder. Release that folder to Prudence so that she can log it in the CM system by Monday afternoon. Then get busy and start designing."   As you hang up the phone, you begin to consider the benefits of keeping a bottle of bourbon in your bottom desk drawer. They threw a party to celebrate the on-time completion of the analysis phase. BB gave a colon-stirring speech on empowerment. And your boss, another 3 mm taller, congratulated his team on the incredible show of unity and teamwork. Finally, the CIO takes the stage to tell everyone that the SEI audit went very well and to thank everyone for studying and shredding the evaluation guides that were passed out. Level 3 now seems assured and will be awarded by June. (Scuttlebutt has it that managers at the level of BB and above are to receive significant bonuses once the SEI awards level 3.)   As the weeks flow by, you and your team work on the design of the system. Of course, you find that the analysis that the design is supposedly based on is flawedno, useless; no, worse than useless. But when you tell your boss that you need to go back and work some more on the analysis to shore up its weaker sections, he simply states, "The analysis phase is over. The only allowable activity is design. Now get back to it."   So, you and your team hack the design as best you can, unsure of whether the requirements have been properly analyzed. Of course, it really doesn't matter much, since the requirements document is still thrashing with weekly revisions, and the marketing department still refuses to meet with you.     The design is a nightmare. Your boss recently misread a book named The Finish Line in which the author, Mark DeThomaso, blithely suggested that design documents should be taken down to code-level detail. "If we are going to be working at that level of detail," you ask, "why don't we simply write the code instead?" "Because then you wouldn't be designing, of course. And the only allowable activity in the design phase is design!" "Besides," he continues, "we have just purchased a companywide license for Dandelion! This tool enables 'Round the Horn Engineering!' You are to transfer all design diagrams into this tool. It will automatically generate our code for us! It will also keep the design diagrams in sync with the code!" Your boss hands you a brightly colored shrinkwrapped box containing the Dandelion distribution. You accept it numbly and shuffle off to your cubicle. Twelve hours, eight crashes, one disk reformatting, and eight shots of 151 later, you finally have the tool installed on your server. You consider the week your team will lose while attending Dandelion training. Then you smile and think, "Any week I'm not here is a good week." Design diagram after design diagram is created by your team. Dandelion makes it very difficult to draw these diagrams. There are dozens and dozens of deeply nested dialog boxes with funny text fields and check boxes that must all be filled in correctly. And then there's the problem of moving classes between packages. At first, these diagram are driven from the use cases. But the requirements are changing so often that the use cases rapidly become meaningless. Debates rage about whether VISITOR or DECORATOR design patterns should be used. One developer refuses to use VISITOR in any form, claiming that it's not a properly object-oriented construct. Someone refuses to use multiple inheritance, since it is the spawn of the devil. Review meetings rapidly degenerate into debates about the meaning of object orientation, the definition of analysis versus design, or when to use aggregation versus association. Midway through the design cycle, the marketing folks announce that they have rethought the focus of the system. Their new requirements document is completely restructured. They have eliminated several major feature areas and replaced them with feature areas that they anticipate customer surveys will show to be more appropriate. You tell your boss that these changes mean that you need to reanalyze and redesign much of the system. But he says, "The analysis phase is system. But he says, "The analysis phase is over. The only allowable activity is design. Now get back to it."   You suggest that it might be better to create a simple prototype to show to the marketing folks and even some potential customers. But your boss says, "The analysis phase is over. The only allowable activity is design. Now get back to it." Hack, hack, hack, hack. You try to create some kind of a design document that might reflect the new requirements documents. However, the revolution of the requirements has not caused them to stop thrashing. Indeed, if anything, the wild oscillations of the requirements document have only increased in frequency and amplitude.   You slog your way through them.   On June 15, the Dandelion database gets corrupted. Apparently, the corruption has been progressive. Small errors in the DB accumulated over the months into bigger and bigger errors. Eventually, the CASE tool just stopped working. Of course, the slowly encroaching corruption is present on all the backups. Calls to the Dandelion technical support line go unanswered for several days. Finally, you receive a brief e-mail from Dandelion, informing you that this is a known problem and that the solution is to purchase the new version, which they promise will be ready some time next quarter, and then reenter all the diagrams by hand.   ****   Then, on July 1 another miracle happens! You are done with the design!   Rather than go to your boss and complain, you stock your middle desk drawer with some vodka.   **** They threw a party to celebrate the on-time completion of the design phase and their graduation to CMM level 3. This time, you find BB's speech so stirring that you have to use the restroom before it begins. New banners and plaques are all over your workplace. They show pictures of eagles and mountain climbers, and they talk about teamwork and empowerment. They read better after a few scotches. That reminds you that you need to clear out your file cabinet to make room for the brandy. You and your team begin to code. But you rapidly discover that the design is lacking in some significant areas. Actually, it's lacking any significance at all. You convene a design session in one of the conference rooms to try to work through some of the nastier problems. But your boss catches you at it and disbands the meeting, saying, "The design phase is over. The only allowable activity is coding. Now get back to it."   ****   The code generated by Dandelion is really hideous. It turns out that you and your team were using association and aggregation the wrong way, after all. All the generated code has to be edited to correct these flaws. Editing this code is extremely difficult because it has been instrumented with ugly comment blocks that have special syntax that Dandelion needs in order to keep the diagrams in sync with the code. If you accidentally alter one of these comments, the diagrams will be regenerated incorrectly. It turns out that "Round the Horn Engineering" requires an awful lot of effort. The more you try to keep the code compatible with Dandelion, the more errors Dandelion generates. In the end, you give up and decide to keep the diagrams up to date manually. A second later, you decide that there's no point in keeping the diagrams up to date at all. Besides, who has time?   Your boss hires a consultant to build tools to count the number of lines of code that are being produced. He puts a big thermometer graph on the wall with the number 1,000,000 on the top. Every day, he extends the red line to show how many lines have been added. Three days after the thermometer appears on the wall, your boss stops you in the hall. "That graph isn't growing quickly enough. We need to have a million lines done by October 1." "We aren't even sh-sh-sure that the proshect will require a m-million linezh," you blather. "We have to have a million lines done by October 1," your boss reiterates. His points have grown again, and the Grecian formula he uses on them creates an aura of authority and competence. "Are you sure your comment blocks are big enough?" Then, in a flash of managerial insight, he says, "I have it! I want you to institute a new policy among the engineers. No line of code is to be longer than 20 characters. Any such line must be split into two or more preferably more. All existing code needs to be reworked to this standard. That'll get our line count up!"   You decide not to tell him that this will require two unscheduled work months. You decide not to tell him anything at all. You decide that intravenous injections of pure ethanol are the only solution. You make the appropriate arrangements. Hack, hack, hack, and hack. You and your team madly code away. By August 1, your boss, frowning at the thermometer on the wall, institutes a mandatory 50-hour workweek.   Hack, hack, hack, and hack. By September 1st, the thermometer is at 1.2 million lines and your boss asks you to write a report describing why you exceeded the coding budget by 20 percent. He institutes mandatory Saturdays and demands that the project be brought back down to a million lines. You start a campaign of remerging lines. Hack, hack, hack, and hack. Tempers are flaring; people are quitting; QA is raining trouble reports down on you. Customers are demanding installation and user manuals; salespeople are demanding advance demonstrations for special customers; the requirements document is still thrashing, the marketing folks are complaining that the product isn't anything like they specified, and the liquor store won't accept your credit card anymore. Something has to give.    On September 15, BB calls a meeting. As he enters the room, his points are emitting clouds of steam. When he speaks, the bass overtones of his carefully manicured voice cause the pit of your stomach to roll over. "The QA manager has told me that this project has less than 50 percent of the required features implemented. He has also informed me that the system crashes all the time, yields wrong results, and is hideously slow. He has also complained that he cannot keep up with the continuous train of daily releases, each more buggy than the last!" He stops for a few seconds, visibly trying to compose himself. "The QA manager estimates that, at this rate of development, we won't be able to ship the product until December!" Actually, you think it's more like March, but you don't say anything. "December!" BB roars with such derision that people duck their heads as though he were pointing an assault rifle at them. "December is absolutely out of the question. Team leaders, I want new estimates on my desk in the morning. I am hereby mandating 65-hour work weeks until this project is complete. And it better be complete by November 1."   As he leaves the conference room, he is heard to mutter: "Empowermentbah!" * * * Your boss is bald; his points are mounted on BB's wall. The fluorescent lights reflecting off his pate momentarily dazzle you. "Do you have anything to drink?" he asks. Having just finished your last bottle of Boone's Farm, you pull a bottle of Thunderbird from your bookshelf and pour it into his coffee mug. "What's it going to take to get this project done? " he asks. "We need to freeze the requirements, analyze them, design them, and then implement them," you say callously. "By November 1?" your boss exclaims incredulously. "No way! Just get back to coding the damned thing." He storms out, scratching his vacant head.   A few days later, you find that your boss has been transferred to the corporate research division. Turnover has skyrocketed. Customers, informed at the last minute that their orders cannot be fulfilled on time, have begun to cancel their orders. Marketing is re-evaluating whether this product aligns with the overall goals of the company. Memos fly, heads roll, policies change, and things are, overall, pretty grim. Finally, by March, after far too many sixty-five hour weeks, a very shaky version of the software is ready. In the field, bug-discovery rates are high, and the technical support staff are at their wits' end, trying to cope with the complaints and demands of the irate customers. Nobody is happy.   In April, BB decides to buy his way out of the problem by licensing a product produced by Rupert Industries and redistributing it. The customers are mollified, the marketing folks are smug, and you are laid off.     Rupert Industries: Project Alpha   Your name is Robert. The date is January 3, 2001. The quiet hours spent with your family this holiday have left you refreshed and ready for work. You are sitting in a conference room with your team of professionals. The manager of the division called the meeting. "We have some ideas for a new project," says the division manager. Call him Russ. He is a high-strung British chap with more energy than a fusion reactor. He is ambitious and driven but understands the value of a team. Russ describes the essence of the new market opportunity the company has identified and introduces you to Jane, the marketing manager, who is responsible for defining the products that will address it. Addressing you, Jane says, "We'd like to start defining our first product offering as soon as possible. When can you and your team meet with me?" You reply, "We'll be done with the current iteration of our project this Friday. We can spare a few hours for you between now and then. After that, we'll take a few people from the team and dedicate them to you. We'll begin hiring their replacements and the new people for your team immediately." "Great," says Russ, "but I want you to understand that it is critical that we have something to exhibit at the trade show coming up this July. If we can't be there with something significant, we'll lose the opportunity."   "I understand," you reply. "I don't yet know what it is that you have in mind, but I'm sure we can have something by July. I just can't tell you what that something will be right now. In any case, you and Jane are going to have complete control over what we developers do, so you can rest assured that by July, you'll have the most important things that can be accomplished in that time ready to exhibit."   Russ nods in satisfaction. He knows how this works. Your team has always kept him advised and allowed him to steer their development. He has the utmost confidence that your team will work on the most important things first and will produce a high-quality product.   * * *   "So, Robert," says Jane at their first meeting, "How does your team feel about being split up?" "We'll miss working with each other," you answer, "but some of us were getting pretty tired of that last project and are looking forward to a change. So, what are you people cooking up?" Jane beams. "You know how much trouble our customers currently have . . ." And she spends a half hour or so describing the problem and possible solution. "OK, wait a second" you respond. "I need to be clear about this." And so you and Jane talk about how this system might work. Some of her ideas aren't fully formed. You suggest possible solutions. She likes some of them. You continue discussing.   During the discussion, as each new topic is addressed, Jane writes user story cards. Each card represents something that the new system has to do. The cards accumulate on the table and are spread out in front of you. Both you and Jane point at them, pick them up, and make notes on them as you discuss the stories. The cards are powerful mnemonic devices that you can use to represent complex ideas that are barely formed.   At the end of the meeting, you say, "OK, I've got a general idea of what you want. I'm going to talk to the team about it. I imagine they'll want to run some experiments with various database structures and presentation formats. Next time we meet, it'll be as a group, and we'll start identifying the most important features of the system."   A week later, your nascent team meets with Jane. They spread the existing user story cards out on the table and begin to get into some of the details of the system. The meeting is very dynamic. Jane presents the stories in the order of their importance. There is much discussion about each one. The developers are concerned about keeping the stories small enough to estimate and test. So they continually ask Jane to split one story into several smaller stories. Jane is concerned that each story have a clear business value and priority, so as she splits them, she makes sure that this stays true.   The stories accumulate on the table. Jane writes them, but the developers make notes on them as needed. Nobody tries to capture everything that is said; the cards are not meant to capture everything but are simply reminders of the conversation.   As the developers become more comfortable with the stories, they begin writing estimates on them. These estimates are crude and budgetary, but they give Jane an idea of what the story will cost.   At the end of the meeting, it is clear that many more stories could be discussed. It is also clear that the most important stories have been addressed and that they represent several months worth of work. Jane closes the meeting by taking the cards with her and promising to have a proposal for the first release in the morning.   * * *   The next morning, you reconvene the meeting. Jane chooses five cards and places them on the table. "According to your estimates, these cards represent about one perfect team-week's worth of work. The last iteration of the previous project managed to get one perfect team-week done in 3 real weeks. If we can get these five stories done in 3 weeks, we'll be able to demonstrate them to Russ. That will make him feel very comfortable about our progress." Jane is pushing it. The sheepish look on her face lets you know that she knows it too. You reply, "Jane, this is a new team, working on a new project. It's a bit presumptuous to expect that our velocity will be the same as the previous team's. However, I met with the team yesterday afternoon, and we all agreed that our initial velocity should, in fact, be set to one perfectweek for every 3 real-weeks. So you've lucked out on this one." "Just remember," you continue, "that the story estimates and the story velocity are very tentative at this point. We'll learn more when we plan the iteration and even more when we implement it."   Jane looks over her glasses at you as if to say "Who's the boss around here, anyway?" and then smiles and says, "Yeah, don't worry. I know the drill by now."Jane then puts 15 more cards on the table. She says, "If we can get all these cards done by the end of March, we can turn the system over to our beta test customers. And we'll get good feedback from them."   You reply, "OK, so we've got our first iteration defined, and we have the stories for the next three iterations after that. These four iterations will make our first release."   "So," says Jane, can you really do these five stories in the next 3 weeks?" "I don't know for sure, Jane," you reply. "Let's break them down into tasks and see what we get."   So Jane, you, and your team spend the next several hours taking each of the five stories that Jane chose for the first iteration and breaking them down into small tasks. The developers quickly realize that some of the tasks can be shared between stories and that other tasks have commonalities that can probably be taken advantage of. It is clear that potential designs are popping into the developers' heads. From time to time, they form little discussion knots and scribble UML diagrams on some cards.   Soon, the whiteboard is filled with the tasks that, once completed, will implement the five stories for this iteration. You start the sign-up process by saying, "OK, let's sign up for these tasks." "I'll take the initial database generation." Says Pete. "That's what I did on the last project, and this doesn't look very different. I estimate it at two of my perfect workdays." "OK, well, then, I'll take the login screen," says Joe. "Aw, darn," says Elaine, the junior member of the team, "I've never done a GUI, and kinda wanted to try that one."   "Ah, the impatience of youth," Joe says sagely, with a wink in your direction. "You can assist me with it, young Jedi." To Jane: "I think it'll take me about three of my perfect workdays."   One by one, the developers sign up for tasks and estimate them in terms of their own perfect workdays. Both you and Jane know that it is best to let the developers volunteer for tasks than to assign the tasks to them. You also know full well that you daren't challenge any of the developers' estimates. You know these people, and you trust them. You know that they are going to do the very best they can.   The developers know that they can't sign up for more perfect workdays than they finished in the last iteration they worked on. Once each developer has filled his or her schedule for the iteration, they stop signing up for tasks.   Eventually, all the developers have stopped signing up for tasks. But, of course, tasks are still left on the board.   "I was worried that that might happen," you say, "OK, there's only one thing to do, Jane. We've got too much to do in this iteration. What stories or tasks can we remove?" Jane sighs. She knows that this is the only option. Working overtime at the beginning of a project is insane, and projects where she's tried it have not fared well.   So Jane starts to remove the least-important functionality. "Well, we really don't need the login screen just yet. We can simply start the system in the logged-in state." "Rats!" cries Elaine. "I really wanted to do that." "Patience, grasshopper." says Joe. "Those who wait for the bees to leave the hive will not have lips too swollen to relish the honey." Elaine looks confused. Everyone looks confused. "So . . .," Jane continues, "I think we can also do away with . . ." And so, bit by bit, the list of tasks shrinks. Developers who lose a task sign up for one of the remaining ones.   The negotiation is not painless. Several times, Jane exhibits obvious frustration and impatience. Once, when tensions are especially high, Elaine volunteers, "I'll work extra hard to make up some of the missing time." You are about to correct her when, fortunately, Joe looks her in the eye and says, "When once you proceed down the dark path, forever will it dominate your destiny."   In the end, an iteration acceptable to Jane is reached. It's not what Jane wanted. Indeed, it is significantly less. But it's something the team feels that can be achieved in the next 3 weeks.   And, after all, it still addresses the most important things that Jane wanted in the iteration. "So, Jane," you say when things had quieted down a bit, "when can we expect acceptance tests from you?" Jane sighs. This is the other side of the coin. For every story the development team implements,   Jane must supply a suite of acceptance tests that prove that it works. And the team needs these long before the end of the iteration, since they will certainly point out differences in the way Jane and the developers imagine the system's behaviour.   "I'll get you some example test scripts today," Jane promises. "I'll add to them every day after that. You'll have the entire suite by the middle of the iteration."   * * *   The iteration begins on Monday morning with a flurry of Class, Responsibilities, Collaborators sessions. By midmorning, all the developers have assembled into pairs and are rapidly coding away. "And now, my young apprentice," Joe says to Elaine, "you shall learn the mysteries of test-first design!"   "Wow, that sounds pretty rad," Elaine replies. "How do you do it?" Joe beams. It's clear that he has been anticipating this moment. "OK, what does the code do right now?" "Huh?" replied Elaine, "It doesn't do anything at all; there is no code."   "So, consider our task; can you think of something the code should do?" "Sure," Elaine said with youthful assurance, "First, it should connect to the database." "And thereupon, what must needs be required to connecteth the database?" "You sure talk weird," laughed Elaine. "I think we'd have to get the database object from some registry and call the Connect() method. "Ah, astute young wizard. Thou perceives correctly that we requireth an object within which we can cacheth the database object." "Is 'cacheth' really a word?" "It is when I say it! So, what test can we write that we know the database registry should pass?" Elaine sighs. She knows she'll just have to play along. "We should be able to create a database object and pass it to the registry in a Store() method. And then we should be able to pull it out of the registry with a Get() method and make sure it's the same object." "Oh, well said, my prepubescent sprite!" "Hay!" "So, now, let's write a test function that proves your case." "But shouldn't we write the database object and registry object first?" "Ah, you've much to learn, my young impatient one. Just write the test first." "But it won't even compile!" "Are you sure? What if it did?" "Uh . . ." "Just write the test, Elaine. Trust me." And so Joe, Elaine, and all the other developers began to code their tasks, one test case at a time. The room in which they worked was abuzz with the conversations between the pairs. The murmur was punctuated by an occasional high five when a pair managed to finish a task or a difficult test case.   As development proceeded, the developers changed partners once or twice a day. Each developer got to see what all the others were doing, and so knowledge of the code spread generally throughout the team.   Whenever a pair finished something significant whether a whole task or simply an important part of a task they integrated what they had with the rest of the system. Thus, the code base grew daily, and integration difficulties were minimized.   The developers communicated with Jane on a daily basis. They'd go to her whenever they had a question about the functionality of the system or the interpretation of an acceptance test case.   Jane, good as her word, supplied the team with a steady stream of acceptance test scripts. The team read these carefully and thereby gained a much better understanding of what Jane expected the system to do. By the beginning of the second week, there was enough functionality to demonstrate to Jane. She watched eagerly as the demonstration passed test case after test case. "This is really cool," Jane said as the demonstration finally ended. "But this doesn't seem like one-third of the tasks. Is your velocity slower than anticipated?"   You grimace. You'd been waiting for a good time to mention this to Jane but now she was forcing the issue. "Yes, unfortunately, we are going more slowly than we had expected. The new application server we are using is turning out to be a pain to configure. Also, it takes forever to reboot, and we have to reboot it whenever we make even the slightest change to its configuration."   Jane eyes you with suspicion. The stress of last Monday's negotiations had still not entirely dissipated. She says, "And what does this mean to our schedule? We can't slip it again, we just can't. Russ will have a fit! He'll haul us all into the woodshed and ream us some new ones."   You look Jane right in the eyes. There's no pleasant way to give someone news like this. So you just blurt out, "Look, if things keep going like they're going, we're not going to be done with everything by next Friday. Now it's possible that we'll figure out a way to go faster. But, frankly, I wouldn't depend on that. You should start thinking about one or two tasks that could be removed from the iteration without ruining the demonstration for Russ. Come hell or high water, we are going to give that demonstration on Friday, and I don't think you want us to choose which tasks to omit."   "Aw forchrisakes!" Jane barely manages to stifle yelling that last word as she stalks away, shaking her head. Not for the first time, you say to yourself, "Nobody ever promised me project management would be easy." You are pretty sure it won't be the last time, either.   Actually, things went a bit better than you had hoped. The team did, in fact, have to drop one task from the iteration, but Jane had chosen wisely, and the demonstration for Russ went without a hitch. Russ was not impressed with the progress, but neither was he dismayed. He simply said, "This is pretty good. But remember, we have to be able to demonstrate this system at the trade show in July, and at this rate, it doesn't look like you'll have all that much to show." Jane, whose attitude had improved dramatically with the completion of the iteration, responded to Russ by saying, "Russ, this team is working hard, and well. When July comes around, I am confident that we'll have something significant to demonstrate. It won't be everything, and some of it may be smoke and mirrors, but we'll have something."   Painful though the last iteration was, it had calibrated your velocity numbers. The next iteration went much better. Not because your team got more done than in the last iteration but simply because the team didn't have to remove any tasks or stories in the middle of the iteration.   By the start of the fourth iteration, a natural rhythm has been established. Jane, you, and the team know exactly what to expect from one another. The team is running hard, but the pace is sustainable. You are confident that the team can keep up this pace for a year or more.   The number of surprises in the schedule diminishes to near zero; however, the number of surprises in the requirements does not. Jane and Russ frequently look over the growing system and make recommendations or changes to the existing functionality. But all parties realize that these changes take time and must be scheduled. So the changes do not cause anyone's expectations to be violated. In March, there is a major demonstration of the system to the board of directors. The system is very limited and is not yet in a form good enough to take to the trade show, but progress is steady, and the board is reasonably impressed.   The second release goes even more smoothly than the first. By now, the team has figured out a way to automate Jane's acceptance test scripts. The team has also refactored the design of the system to the point that it is really easy to add new features and change old ones. The second release was done by the end of June and was taken to the trade show. It had less in it than Jane and Russ would have liked, but it did demonstrate the most important features of the system. Although customers at the trade show noticed that certain features were missing, they were very impressed overall. You, Russ, and Jane all returned from the trade show with smiles on your faces. You all felt as though this project was a winner.   Indeed, many months later, you are contacted by Rufus Inc. That company had been working on a system like this for its internal operations. Rufus has canceled the development of that system after a death-march project and is negotiating to license your technology for its environment.   Indeed, things are looking up!

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  • Q1 2010 New Feature: Paging with RadGridView for Silverlight and WPF

    We are glad to announce that the Q1 2010 Release has added another weapon to RadGridViews growing arsenal of features. This is the brand new RadDataPager control which provides the user interface for paging through a collection of data. The good news is that RadDataPager can be used to page any collection. It does not depend on RadGridView in any way, so you will be free to use it with the rest of your ItemsControls if you chose to do so. Before you read on, you might want to download the samples solution that I have attached. It contains a sample project for every scenario that I will discuss later on. Looking at the code while reading will make things much easier for you. There is something for everyone among the 10 Visual Studio projects that are included in the solution. So go and grab it. I. Paging essentials The single most important piece of software concerning paging in Silverlight is the System.ComponentModel.IPagedCollectionView interface. Those of you who are on the WPF front need not worry though. As you might already know, Teleriks Silverlight and WPF controls is share the same code-base. Since WPF does not contain a similar interface, Telerik has provided its own Telerik.Windows.Data.IPagedCollectionView. The IPagedCollectionView interface contains several important members which are used by RadGridView to perform the actual paging. Silverlight provides a default implementation of this interface which, naturally, is called PagedCollectionView. You should definitely take a look at its source code in case you are interested in what is going on under the hood. But this is not a prerequisite for our discussion. The WPF default implementation of the interface is Teleriks QueryableCollectionView which, among many other interfaces, implements IPagedCollectionView. II. No Paging In order to gradually build up my case, I will start with a very simple example that lacks paging whatsoever. It might sound stupid, but this will help us build on top of this paging-devoid example. Let us imagine that we have the simplest possible scenario. That is a simple IEnumerable and an ItemsControl that shows its contents. This will look like this: No Paging IEnumerable itemsSource = Enumerable.Range(0, 1000); this.itemsControl.ItemsSource = itemsSource; XAML <Border Grid.Row="0" BorderBrush="Black" BorderThickness="1" Margin="5">     <ListBox Name="itemsControl"/> </Border> <Border Grid.Row="1" BorderBrush="Black" BorderThickness="1" Margin="5">     <TextBlock Text="No Paging"/> </Border> Nothing special for now. Just some data displayed in a ListBox. The two sample projects in the solution that I have attached are: NoPaging_WPF NoPaging_SL3 With every next sample those two project will evolve in some way or another. III. Paging simple collections The single most important property of RadDataPager is its Source property. This is where you pass in your collection of data for paging. More often than not your collection will not be an IPagedCollectionView. It will either be a simple List<T>, or an ObservableCollection<T>, or anything that is simply IEnumerable. Unless you had paging in mind when you designed your project, it is almost certain that your data source will not be pageable out of the box. So what are the options? III. 1. Wrapping the simple collection in an IPagedCollectionView If you look at the constructors of PagedCollectionView and QueryableCollectionView you will notice that you can pass in a simple IEnumerable as a parameter. Those two classes will wrap it and provide paging capabilities over your original data. In fact, this is what RadGridView does internally. It wraps your original collection in an QueryableCollectionView in order to easily perform many useful tasks such as filtering, sorting, and others, but in our case the most important one is paging. So let us start our series of examples with the most simplistic one. Imagine that you have a simple IEnumerable which is the source for an ItemsControl. Here is how to wrap it in order to enable paging: Silverlight IEnumerable itemsSource = Enumerable.Range(0, 1000); var pagedSource = new PagedCollectionView(itemsSource); this.radDataPager.Source = pagedSource; this.itemsControl.ItemsSource = pagedSource; WPF IEnumerable itemsSource = Enumerable.Range(0, 1000); var pagedSource = new QueryableCollectionView(itemsSource); this.radDataPager.Source = pagedSource; this.itemsControl.ItemsSource = pagedSource; XAML <Border Grid.Row="0"         BorderBrush="Black"         BorderThickness="1"         Margin="5">     <ListBox Name="itemsControl"/> </Border> <Border Grid.Row="1"         BorderBrush="Black"         BorderThickness="1"         Margin="5">     <telerikGrid:RadDataPager Name="radDataPager"                               PageSize="10"                              IsTotalItemCountFixed="True"                              DisplayMode="All"/> This will do the trick. It is quite simple, isnt it? The two sample projects in the solution that I have attached are: PagingSimpleCollectionWithWrapping_WPF PagingSimpleCollectionWithWrapping_SL3 III. 2. Binding to RadDataPager.PagedSource In case you do not like this approach there is a better one. When you assign an IEnumerable as the Source of a RadDataPager it will automatically wrap it in a QueryableCollectionView and expose it through its PagedSource property. From then on, you can attach any number of ItemsControls to the PagedSource and they will be automatically paged. Here is how to do this entirely in XAML: Using RadDataPager.PagedSource <Border Grid.Row="0"         BorderBrush="Black"         BorderThickness="1" Margin="5">     <ListBox Name="itemsControl"              ItemsSource="{Binding PagedSource, ElementName=radDataPager}"/> </Border> <Border Grid.Row="1"         BorderBrush="Black"         BorderThickness="1"         Margin="5">     <telerikGrid:RadDataPager Name="radDataPager"                               Source="{Binding ItemsSource}"                              PageSize="10"                              IsTotalItemCountFixed="True"                              DisplayMode="All"/> The two sample projects in the solution that I have attached are: PagingSimpleCollectionWithPagedSource_WPF PagingSimpleCollectionWithPagedSource_SL3 IV. Paging collections implementing IPagedCollectionView Those of you who are using WCF RIA Services should feel very lucky. After a quick look with Reflector or the debugger we can see that the DomainDataSource.Data property is in fact an instance of the DomainDataSourceView class. This class implements a handful of useful interfaces: ICollectionView IEnumerable INotifyCollectionChanged IEditableCollectionView IPagedCollectionView INotifyPropertyChanged Luckily, IPagedCollectionView is among them which lets you do the whole paging in the server. So lets do this. We will add a DomainDataSource control to our page/window and connect the items control and the pager to it. Here is how to do this: MainPage <riaControls:DomainDataSource x:Name="invoicesDataSource"                               AutoLoad="True"                               QueryName="GetInvoicesQuery">     <riaControls:DomainDataSource.DomainContext>         <services:ChinookDomainContext/>     </riaControls:DomainDataSource.DomainContext> </riaControls:DomainDataSource> <Border Grid.Row="0"         BorderBrush="Black"         BorderThickness="1"         Margin="5">     <ListBox Name="itemsControl"              ItemsSource="{Binding Data, ElementName=invoicesDataSource}"/> </Border> <Border Grid.Row="1"         BorderBrush="Black"         BorderThickness="1"         Margin="5">     <telerikGrid:RadDataPager Name="radDataPager"                               Source="{Binding Data, ElementName=invoicesDataSource}"                              PageSize="10"                              IsTotalItemCountFixed="True"                              DisplayMode="All"/> By the way, you can replace the ListBox from the above code snippet with any other ItemsControl. It can be RadGridView, it can be the MS DataGrid, you name it. Essentially, RadDataPager is sending paging commands to the the DomainDataSource.Data. It does not care who, what, or how many different controls are bound to this same Data property of the DomainDataSource control. So if you would like to experiment with this, you can throw in any number of other ItemsControls next to the ListBox, bind them in the same manner, and all of them will be paged by our single RadDataPager. Furthermore, you can throw in any number of RadDataPagers and bind them to the same property. Then when you page with any one of them will automatically update all of the rest. The whole picture is simply beautiful and we can do all of this thanks to WCF RIA Services. The two sample projects (Silverlight only) in the solution that I have attached are: PagingIPagedCollectionView PagingIPagedCollectionView.Web IV. Paging RadGridView While you can replace the ListBox in any of the above examples with a RadGridView, RadGridView offers something extra. Similar to the DomainDataSource.Data property, the RadGridView.Items collection implements the IPagedCollectionView interface. So you are already thinking: Then why not bind the Source property of RadDataPager to RadGridView.Items? Well thats exactly what you can do and you will start paging RadGridView out-of-the-box. It is as simple as that, no code-behind is involved: MainPage <Border Grid.Row="0"         BorderBrush="Black"         BorderThickness="1" Margin="5">     <telerikGrid:RadGridView Name="radGridView"                              ItemsSource="{Binding ItemsSource}"/> </Border> <Border Grid.Row="1"         BorderBrush="Black"         BorderThickness="1"         Margin="5">     <telerikGrid:RadDataPager Name="radDataPager"                               Source="{Binding Items, ElementName=radGridView}"                              PageSize="10"                              IsTotalItemCountFixed="True"                              DisplayMode="All"/> The two sample projects in the solution that I have attached are: PagingRadGridView_SL3 PagingRadGridView_WPF With this last example I think I have covered every possible paging combination. In case you would like to see an example of something that I have not covered, please let me know. Also, make sure you check out those great online examples: WCF RIA Services with DomainDataSource Paging Configurator Endless Paging Paging Any Collection Paging RadGridView Happy Paging! Download Full Source Code Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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