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• Can't manage iPod from linux anymore

  - by kemp

  I used to be able to see and manage my iPod with different softwares: Amarok, Rhythmbox, GTKPod. The device is a nano 1st generation 4gb. Currently it mounts regularly and can be accessed from the file system, but I get this in dmesg: [ 1547.617891] scsi 11:0:0:0: Direct-Access Apple iPod 1.62 PQ: 0 ANSI: 0 [ 1547.619103] sd 11:0:0:0: Attached scsi generic sg2 type 0 [ 1547.620478] sd 11:0:0:0: [sdb] Adjusting the sector count from its reported value: 7999488 [ 1547.620494] sd 11:0:0:0: [sdb] 7999487 512-byte hardware sectors: (4.09 GB/3.81 GiB) [ 1547.621718] sd 11:0:0:0: [sdb] Write Protect is off [ 1547.621726] sd 11:0:0:0: [sdb] Mode Sense: 68 00 00 08 [ 1547.621732] sd 11:0:0:0: [sdb] Assuming drive cache: write through [ 1547.623591] sd 11:0:0:0: [sdb] Adjusting the sector count from its reported value: 7999488 [ 1547.624993] sd 11:0:0:0: [sdb] Assuming drive cache: write through [ 1547.625003] sdb: sdb1 sdb2 [ 1547.629686] sd 11:0:0:0: [sdb] Attached SCSI removable disk [ 1548.084026] FAT: utf8 is not a recommended IO charset for FAT filesystems, filesystem will be case sensitive! [ 1548.369502] FAT: utf8 is not a recommended IO charset for FAT filesystems, filesystem will be case sensitive! [ 1548.504358] FAT: invalid media value (0x2f) [ 1548.504363] VFS: Can't find a valid FAT filesystem on dev sdb1. [ 1548.945173] FAT: utf8 is not a recommended IO charset for FAT filesystems, filesystem will be case sensitive! [ 1548.945179] FAT: invalid media value (0x2f) [ 1548.945182] VFS: Can't find a valid FAT filesystem on dev sdb1. [ 1610.092886] usb 2-6: USB disconnect, address 9 The only application that can access it (partially) is Rhythmbox. I say partially because I can transfer files to the iPod but can't remove or modify them. Also one transfer didn't finish and only 9 out of 16 songs were delivered to the device. All other softwares I tried (GTKPod, Amarok, Songbird) don't even detect it. What can I do to troubleshoot this? EDIT: # fdisk -l /dev/sdb Disk /dev/sdb: 4095 MB, 4095737344 bytes 241 heads, 62 sectors/track, 535 cylinders Units = cylinders of 14942 * 512 = 7650304 bytes Disk identifier: 0x20202020 Device Boot Start End Blocks Id System /dev/sdb1 1 11 80293+ 0 Empty Partition 1 has different physical/logical beginnings (non-Linux?): phys=(0, 1, 1) logical=(0, 1, 2) Partition 1 has different physical/logical endings: phys=(9, 254, 63) logical=(10, 181, 8) Partition 1 does not end on cylinder boundary. /dev/sdb2 11 536 3919415+ b W95 FAT32 Partition 2 has different physical/logical beginnings (non-Linux?): phys=(10, 0, 7) logical=(10, 181, 15) Partition 2 has different physical/logical endings: phys=(497, 240, 62) logical=(535, 88, 61) EDIT2: The "before" state is hard to tell, it was a lot of updates ago. Haven't been using my iPod for a while so I can't say when exactly it stopped working. I'm sure Amarok was still at version 1.X but can't remember when it was. My current system is debian testing fully updated. NOTE: just noticed that if I mount the device manually instead of letting nautilus automount it, I can see it again on GTKPod but still not on Banshee AND it's vanished from Rhythmbox...

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• HP DL580 G5 Hyper-V networking problem

  - by mr-perfect

  Hi I have installed the hyper-v role on a DL580 G5 cluster. The host operating system is a server 2008 x64 patched to the maximum. Everything has gone fine, but if I install a guest operating system, actually a windows server 2008 x64 I can't reach the network from it. It send many packets, but don't received any, so I can't ping the external network as well. I have installed the latest drivers to the server and unintalled the network configuration utility from the physical server, but no luck. I added a legacy adapter to the guest binded to the same phisycal adapter on the host machine but it can't help Any idea welcome...

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• OSX 10.8 Corrupted User Account Using Launchctl

  - by Scott

  I used the following command: launchctl unload -w /System/Library/LaunchAgents/com.apple.notificationcenterui.plist in an attempt to disable notification center. I'm not sure that I got all of the commands right and appear to have corrupted the account that I executed it from - I get a grey screen when I try to login on that account. Fortunately I have another account on the machine with admin privileges so I can still use the machine. I would however like to restore the account to a working condition preferably without having to resort to a complete system restore from my time machine backup. Is there a way of diagnosing the current status of this launchagent and returning it to its original state?

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• Disable Memory Modules In BIOS for Testing Purposes (Optimize Nehalem/Gulftown Memory Performance)

  - by Bob

  I recently acquired an HP Z800 with two Intel Xeon X5650 (Gulftown) 6 core processors. The person that configured the system chose 16GB (8 x 2GB DDR3-1333). I'm assuming this person was unaware these processors have 3 memory channels and to optimize memory performance one should choose memory in multiples of three. Based on this information, I have a question: By entering the BIOS, can I disable the bank on each processor that has the single memory module? If so, will this have any adverse effects or behave differently than physically removing the modules? I ask due to the fact that I prefer to store the extra memory in the system if it truly behaves as if the memory is not even there. Also, I see this as an opportunity to test 12GB vs. 16GB to see if there is a noticeable difference. Note: According to http://www.delltechcenter.com/page/04-08-2009+-+Nehalem+and+Memory+Configurations?t=anon, the current configuration reduces the overall data transfer speed to 1066 and in addition, the memory bandwidth goes down by about 23%.

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• SSIS DSN Not Showing as ODBC Data Source

  - by user1114330

  I have been following the directions here: http://social.msdn.microsoft.com/Forums/en-US/sqlintegrationservices/thread/05ccd778-b78c-4a83-a10a-c4ae412cc6e4 And ran into a problem where my System DSN is not showing up as a ODBC provider. I found this which seemed promising: http://support.microsoft.com/kb/2000277 I was not able to delete the key but followed but I did what was suggested: "If unable to delete the key, double-click the key and erase the Data value entered. Once done, the value should read ' (value not set) '" However, after following the instructions my System DSN still does not appear as an option. The USER DSN however does show...has shown but does not work as I get a permissions error. Any ideas?

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• Cannot set MemOpMode or ProcVirtualization with syscfg.exe

  - by EGr

  When attempting to set MemOpMode or ProcVirtualization with syscfg.exe, I get the following error: C:\Users\EGr>syscfg --MemOpMode=AdvEccMode System Services or CSIOR disabled In the past, I have been told that this can be resolved by forcefully reinstalling the Dell Lifecycle controller firmware, and then trying again; however, I cannot find my notes on how to do that. Has anyone ever run into this issue, and does anyone know how I can fix it? If it is possible to forcefully reinstall the firmware, how would I do that? I've tried running the installer, but it fails after running for ~2 min. I believe there is a way to fix this as well, by adding/modifying a registry value at HKLM\System\Control\CurrentControlSet\Services\IPMIDRV (that might not be the correct path, but I know it is IPMIDRV). Is this a common issue? What is the actual cause of it?

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• Create mirror software raid with bad blocks hdd. How to check data integrity?

  - by rumburak

  There is error in System event log like this one: "The device, \Device\Harddisk1\DR1, has a bad block." Because of above I created Raid 1 on this disk and other one. I'm using Windows Server 2008 R2 software RAID volumes. Volume in Disk Manager is marked as "Failed Redundancy" and "At Risk". I could command to "Reactivate Disk" and it's starts to re-sync, but after a while it stops and returns to previous state. It stops re-sync on bad block on old disk and creates same error in System event log. Old disk status is Errors, new disk status is Online. How can I check that there is exact copy of the old disk on new one ? It is server machine so I would prefer to keep it running during this check.

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• Child Folder inheriting a permission that parent folder does not have (NTFS)

  - by just.another.programmer

  I'm reconfiguring roaming profiles on my network to use proper NTFS security settings according to this article. I have reset the following permissions on the roaming profile parent folder: CREATOR OWNER, Full Control, Subfolder and files only User group with profiles, List folder, Create folders, This folder only System, Full Control, This folder, subfolders, and files Then I select one of the actual roaming profile folders and follow these steps to fix the NTFS settings: Click Security, Advanced Uncheck "Allow inheritable permissions..." Choose "Remove..." Recheck "Allow inheritable permissions..." Click "Apply" After I choose apply, I get the following permissions listed on the roaming profile folder: Administrators (MYDOMAIN\Administrators) Full Control, This folder only CREATOR OWNER, Full Control, Subfolders and files only System, Full Control, This folder, subfolders, and files Where is the Administrators entry coming from!? There is an entry on the root of the drive for Administrators to have full control, but the Roaming Profile Parent folder is not set to inherit any permissions, and it does not have the administrators permission.

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• UEC - Can the Cluster Controller and Storage Controller be seperate systems?

  - by Jeremy Hajek

  My department is implementing an Ubuntu Enterprise Cloud. I have done the testing and am quite comfortable with the 4 pieces, CC/SC, CLC, WS, NC. Looking at various documents below it appears the the Storage Controller and Cluster Controller (eucalyptus-sc and eucalyptus-cc) are always installed on the same system. My question is this: can I install the storage controller and the cluster controller on separate systems? http://open.eucalyptus.com/wiki/EucalyptusAdvanced_v2.0 the picture indicates that cc and sc are two different machines http://www.canonical.com/sites/default/files/active/Whitepaper-UbuntuEnterpriseCloudArchitecture-v1.pdf P.10 1st paragraph uses the word "machine(s)" http://software.intel.com/file/31966 P. 8 indicates the same separate architecture BUT... https://help.ubuntu.com/community/UEC/PackageInstallSeparate indicates below that the SC and CC are to be on the same system.

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• ethernet not working

  - by good boy

  i wanted to know how do i setup an ethernet connection on a laptop,my isp gave me a telephone like cable which fits the ethernet port. i guess its the ethernet cable. when i connect it, nothing happens on the pc the ethernet card(realtek pcie gbe family controller) says cable not plugged in. i am using wired connection for first time.the system is completely stable with softwares .the drivers are also automatically updated through a manufacturer installed update system. the isp says there must be some sort of light on the port. whats the problem? how do get it working.

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• CentOS 5.7 keeps rebooting after fresh installation

  - by Wagner Maestrelli

  I have just installed CentOS 5.7 x86_64 on a new computer. The installation went on without any issues. But, after it finnished, the machine started to show an awkward behaviour: it restarts every time it tries to boot. It happens after all the services have been started. The screen just goes black and it shows an error message from the monitor: Input not supported. And then it reboots. I took a look at the logs, but I couldn't manage to find anything. Any help? Update Before doing the hardware diagnosis, as pointed out, I decided to make some tests. First, I changed the runlevel to 3, adding the 3 parameter at the end of the kernel command. Then, after logging in in text mode, I checked the xorg.conf file out for some problems regarding the screen resolution. There was nothing unexpected set. Well, if there had to be a problem with it, I couldn't start the X server at the command line, right? So, I typed startx and Gnome started! So, probably, it's not an issue with the screen resolution, I suppose. Then I selected the Log Out root... Gnome menu option and something odd happened: the screen went black, the Input not supported monitor error message was displayed and the system rebooted. Yes, the same problem I was having while trying to boot! After that, I decided to try yet another test: I removed the rhgb quiet parameters from the kernel command to see if some error would show up. Well, to my surprise, the boot went on without problems! The Gnome login screen showed up, I logged in and the session started. But then I selected the Shut Down... menu option and guess what? Same problem: black screen, same monitor error and the system rebooted. Yes, it rebooted, it did not shut down. I repeated both of the tests and the behaviours were the same. I really don't know what's going on. It seems to be an issue regarding the changing of the screen mode or something like that. Any ideas? Could this be a hardware problem? Or does it seem to be something regarding the system configuration?

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• Wiping out user and/or root password in embedded linux

  - by TryTryAgain

  We have a security camera system running an embedded linux. It boots with Lilo as a bootloader and has no tty access once booted. I don't know any username either. SSH/22 is open, but I don't think brute force is an option. I have tried all the common tricks to reset a linux user password (boot from the bootloader in single user mode = doesn't happen, still prompts for user login, boot to a live cd = can't access the file system...it's all loop files and other binary, etc etc), but they are all not possible as it is an embedded linux setup the way it is. Any help/suggestions would be appreciated. Thanks

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• How to compare speed of graphics cards in Windows desktop environment?

  - by Al Kepp

  I use Windows 7 and Intel Core i3 CPU with integrated graphics. My problem is that it eats valuable system RAM for display. I can replace it with an old PCIe Radeon X700, so all system RAM will be usable for applications. The question is if an old Radeon X700 is comparable in W7 desktop speed to a new integrated i3 graphics. Are there any test programs which compare the speed of graphic cards in Windows 7 desktop environment (i.e. no Direct3D games, just Windows desktop)? (According to Tomshardware, Radeon X700 is probably even faster than Core i3 in 3D. But there are no native WDDM 1.1 W7 drivers for X700, only WDDM 1.0 Vista drivers are available.)

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• Change the default route without affecting existing TCP connections

  - by Patrick Horn

  Let's say I have two public network addresses on my server: one NAT through an ISP (192.168.99.0/24), and a VPN through a different ISP (192.168.1.0/24), already configured with a per-host route to the VPN server through my ISP. Here is my initial routing table. I am currently routing through my ISP on subnet 192.168.99.0/24. $ route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 192.168.99.1 0.0.0.0 UG 0 0 0 eth1 55.66.77.88 192.168.99.1 255.255.255.255 UGH 0 0 0 eth1 192.168.99.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 tap0 Now, I want new TCP connections to switch to my 192.168.1.0/24 so I type the following: $ route add -net 0.0.0.0 gw 192.168.1.1 dev tap0 When I do this, it causes some long-standing TCP connections to hang. Is there a way to I safely change the default interface for new connections, while allowing existing TCP connections to use the old route (i.e. do I need enable some sort of stateful routing table)? I am okay with a solution that only works with established TCP connections, and I don't care how hacky it is. For example, if there is a way to add temporary iptables rules for existing connections to force them over the old route. But there has to be some way to do this. EDIT: Just a note about a simple "route add -host ... " for existing connections: this solution would work if I am fine with leaving a subset of IPs on the old interface. However, in my application, this actually doesn't solve my problem because I want to allow new connections to come on the new interface even if they have the same source IP. I'm now looking at using the "ip route" command to set source-based routing rules.

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• Windows 7 using exactly HALF the installed memory

  - by Nathan Ridley

  I've taken this directly from system information: Installed Physical Memory (RAM) 4.00 GB Total Physical Memory 2.00 GB Available Physical Memory 434 MB Total Virtual Memory 5.10 GB Available Virtual Memory 1.19 GB Page File Space 3.11 GB Also the BIOS reports a full 4GB available. Note the 4gb installed, yet 2gb total. I understand that on a 32 bit operating system, you'll never get the full 4gb of ram, however typically you'll get in the range of 2.5-3.2gb of ram. I have only 2gb available! My swap file goes nuts when I do anything! Note that I have dual SLI nvidia video cards, each with 512mb of on board ram, though I have the SLI feature turned off. Anybody know why Windows might claim that I have exactly 2gb of ram total? Note: previously asked on SuperUser, but closed as "belongs on superuser" before this site opened: http://serverfault.com/questions/39603/windows-7-using-exactly-half-the-installed-memory (I still need an answer!)

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• Cannot access host from a virtualbox guest using bridged adapter

  - by David Dai

  I have a windows 7 host with firewall turned off. And I have a windowsXP guest running on Virtualbox 4.2.4r81684. In my windowsXP guest I tried to connect to the FTP server on my host machine(which used to work well) but it didn't work. I tried to ping my host machine, but it didn't work either. Then I tried to ping my guest from host, it worked well. my guest ip is :192.168.1.95 my host ip is : 192.168.1.9 route table on guest machine is this: C:\Documents and Settings\wenlong>route PRINT =========================================================================== Interface List 0x1 ........................... MS TCP Loopback interface 0x2 ...08 00 27 66 54 6c ...... AMD PCNET Family PCI Ethernet Adapter #2 - Packe t Scheduler Miniport =========================================================================== =========================================================================== Active Routes: Network Destination Netmask Gateway Interface Metric 0.0.0.0 0.0.0.0 192.168.1.1 192.168.1.95 20 127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1 192.168.1.0 255.255.255.0 192.168.1.95 192.168.1.95 20 192.168.1.95 255.255.255.255 127.0.0.1 127.0.0.1 20 192.168.1.255 255.255.255.255 192.168.1.95 192.168.1.95 20 224.0.0.0 240.0.0.0 192.168.1.95 192.168.1.95 20 255.255.255.255 255.255.255.255 192.168.1.95 192.168.1.95 1 Default Gateway: 192.168.1.1 =========================================================================== Persistent Routes: None arp cache is this: C:\Documents and Settings\wenlong>arp -a Interface: 192.168.1.95 --- 0x2 Internet Address Physical Address Type 192.168.1.1 00-26-f2-60-3c-04 dynamic 192.168.1.9 90-e6-ba-c2-90-2f dynamic It's strange because there was no problem days before and I didn't make any changes to the setting. could anybody help? PS. the guest can communicate with other machines in the LAN(for example 192.168.1.114) ok. it just cannot connect to the host machine.

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• Is there an unintrusive antivirus program that I can ask to scan object on demand only? [closed]

  - by Faken

  Possible Duplicate: Recommended offline on-demand virus scanners I'm looking for an unintrusive antivirus program that I can get to run scans on suspicious objects on demand and only on demand. Most other antivirus programs install many layers of protection and things running in the background and preform regular updates and system scans at inconvenient times. I want an antivirus program that I can simply right click and object and select "scan for viruses" and nothing more. Is there a reliable antivirus program out there that offers this and only this without the automatic updates, background processes, and intrusive automatic system scans? Note: this is for Windows.

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• Java version indicates SE 6, Java Control Panel SE 8

  - by Mariogs

  So I'm trying to get the Java 7 as the default version on my machine, running Mac OS X 10.9.3. When I run: java -version I get: java version "1.6.0_65" Java(TM) SE Runtime Environment (build 1.6.0_65-b14-462-11M4609) Java HotSpot(TM) 64-Bit Server VM (build 20.65-b04-462, mixed mode) When I run: javac -version I get: javac 1.6.0_65 When I go into System Preferences -- Java -- Update, I see: Your system has the recommended vesion of Java. Java 8 Update 05. I guess I have a few questions: 1) Why does my Java Control Panel claim I have Java 8, but my work in the terminal (when checking my Java version) says otherwise? 2) I just downloaded the .dmg file for Java SE 7 from Oracle's site and installed, though it's nowhere to be seen... Thanks for the help, Mariogs

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• Location of truetype fonts

  - by StackedCrooked

  I would like to create a small script that installs a few truetype fonts on the user's system. On my Ubuntu machine the truetype fonts are located at /usr/share/fonts/truetype. However, I'm not sure if this location is the same on all machines. Is there a way to find out where truetypes fonts are stored on any Linux system? Update After some research I found that the path usr/share/fonts/truetype is specified in the XML file /etc/fonts/fonts.conf. It's an XML file, so I can use XPath to get the dir: xpath -q -e 'fontconfig/dir[1]/text()[1]' /etc/fonts/fonts.conf I don't know however if this file will exist on all (or most) Linux systems.

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• Chrome shows "The site's security certificate is not trusted" error

  - by Emerald214

  From this morning I get this error whenever I access Google Docs and some websites. My system datetime is correct and I checked "Automatically from the Internet". My BIOS is OK. I cleared everything (cache, cookie, private data) in Chrome and restarted OS but nothing changes. How to fix it? Firefox works but Chrome has that problem. The site's security certificate is not trusted! You attempted to reach docs.google.com, but the server presented a certificate issued by an entity that is not trusted by your computer's operating system. This may mean that the server has generated its own security credentials, which Google Chrome cannot rely on for identity information, or an attacker may be trying to intercept your communications. You cannot proceed because the website operator has requested heightened security for this domain.

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• SSSD Authentication

  - by user24089

  I just built a test server running OpenSuSE 12.1 and am trying to learn how configure sssd, but am not sure where to begin to look for why my config cannot allow me to authenticate. server:/etc/sssd # cat sssd.conf [sssd] config_file_version = 2 reconnection_retries = 3 sbus_timeout = 30 services = nss,pam domains = test.local [nss] filter_groups = root filter_users = root reconnection_retries = 3 [pam] reconnection_retries = 3 # Section created by YaST [domain/mose.cc] access_provider = ldap ldap_uri = ldap://server.test.local ldap_search_base = dc=test,dc=local ldap_schema = rfc2307bis id_provider = ldap ldap_user_uuid = entryuuid ldap_group_uuid = entryuuid ldap_id_use_start_tls = True enumerate = False cache_credentials = True chpass_provider = krb5 auth_provider = krb5 krb5_realm = TEST.LOCAL krb5_kdcip = server.test.local server:/etc # cat ldap.conf base dc=test,dc=local bind_policy soft pam_lookup_policy yes pam_password exop nss_initgroups_ignoreusers root,ldap nss_schema rfc2307bis nss_map_attribute uniqueMember member ssl start_tls uri ldap://server.test.local ldap_version 3 pam_filter objectClass=posixAccount server:/etc # cat nsswitch.conf passwd: compat sss group: files sss hosts: files dns networks: files dns services: files protocols: files rpc: files ethers: files netmasks: files netgroup: files publickey: files bootparams: files automount: files ldap aliases: files shadow: compat server:/etc # cat krb5.conf [libdefaults] default_realm = TEST.LOCAL clockskew = 300 [realms] TEST.LOCAL = { kdc = server.test.local admin_server = server.test.local database_module = ldap default_domain = test.local } [logging] kdc = FILE:/var/log/krb5/krb5kdc.log admin_server = FILE:/var/log/krb5/kadmind.log default = SYSLOG:NOTICE:DAEMON [dbmodules] ldap = { db_library = kldap ldap_kerberos_container_dn = cn=krbContainer,dc=test,dc=local ldap_kdc_dn = cn=Administrator,dc=test,dc=local ldap_kadmind_dn = cn=Administrator,dc=test,dc=local ldap_service_password_file = /etc/openldap/ldap-pw ldap_servers = ldaps://server.test.local } [domain_realm] .test.local = TEST.LOCAL [appdefaults] pam = { ticket_lifetime = 1d renew_lifetime = 1d forwardable = true proxiable = false minimum_uid = 1 clockskew = 300 external = sshd use_shmem = sshd } If I log onto the server as root I can su into an ldap user, however if I try to console locally or ssh remotely I am unable to authenticate. getent doesn't show the ldap entries for users, Im not sure if I need to look at LDAP, nsswitch, or what: server:~ # ssh localhost -l test Password: Password: Password: Permission denied (publickey,keyboard-interactive). server:~ # su test test@server:/etc> id uid=1000(test) gid=100(users) groups=100(users) server:~ # tail /var/log/messages Nov 24 09:36:44 server login[14508]: pam_sss(login:auth): system info: [Client not found in Kerberos database] Nov 24 09:36:44 server login[14508]: pam_sss(login:auth): authentication failure; logname=LOGIN uid=0 euid=0 tty=/dev/ttyS1 ruser= rhost= user=test Nov 24 09:36:44 server login[14508]: pam_sss(login:auth): received for user test: 4 (System error) Nov 24 09:36:44 server login[14508]: FAILED LOGIN SESSION FROM /dev/ttyS1 FOR test, System error server:~ # vi /etc/pam.d/common-auth auth required pam_env.so auth sufficient pam_unix2.so auth required pam_sss.so use_first_pass server:~ # vi /etc/pam.d/sshd auth requisite pam_nologin.so auth include common-auth account requisite pam_nologin.so account include common-account password include common-password session required pam_loginuid.so session include common-session session optional pam_lastlog.so silent noupdate showfailed

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• How can I centralise MySQL data between 3 or more geographically separate servers?

  - by Andy Castles

  To explain the background to the question: We have a home-grown PHP application (for running online language-learning courses) running on a Linux server and using MySQL on localhost for saving user data (e.g. results of tests taken, marks of submitted work, time spent on different pages in the courses, etc). As we have students from different geographic locations we currently have 3 virtual servers hosted close to those locations (Spain, UK and Hong Kong) and users are added to the server closest to them (they access via different URLs, e.g. europe.domain.com, uk.domain.com and asia.domain.com). This works but is an administrative nightmare as we have to remember which server a particular user is on, and users can only connect to one server. We would like to somehow centralise the information so that all users are visible on any of the servers and users could connect to any of the 3 servers. The question is, what method should we use to implement this. It must be an issue that that lots of people have encountered but I haven't found anything conclusive after a fair bit of Googling around. The closest I have seen to solutions are: something like master-master replication, but I have read so many posts suggesting that this is not a good idea as things like auto_increment fields can break. circular replication, this sounded perfect but to quote from O'Reilly's High Performance MySQL, "In general, rings are brittle and best avoided" We're not against rewriting code in the application to make it work with whatever solution is required but I am not sure if replication is the correct thing to use. Thanks, Andy P.S. I should add that we experimented with writes to a central database and then using reads from a local database but the response time between the different servers for writing was pretty bad and it's also important that written data is available immediately for reading so if replication is too slow this could cause out-of-date data to be returned. Edit: I have been thinking about writing my own rudimentary replication script which would involve something like having each user given a server ID to say which is his "home server", e.g. users in asia would be marked as having the Hong Kong server as their own server. Then the replication scripts (which would be a PHP script set to run as a cron job reasonably frequently, e.g. every 15 minutes or so) would run independently on each of the servers in the system. They would go through the database and distribute any information about users with the "home server" set to the server that the script is running on to all of the other databases in the system. They would also need to suck new information which has been added to any of the other databases on the system where the "home server" flag is the server where the script is running. I would need to work out the details and build in the logic to deal with conflicts but I think it would be possible, however I wanted to make sure that there is not a correct solution for this already out there as it seems like it must be a problem that many people have already come across.

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• How do you use environment variables, such as %CommonProgramFiles%, in the PATH and have them recognized by services.exe?

  - by Brad Knowles

  I'm trying to add C:\Program Files\Common Files\xxx\xxx to the system PATH environment variable by appending %CommonProgramFiles%\xxx\xxx to the existing path. After rebooting, I open a command prompt and check the PATH. It expands correctly. However, when using Process Explorer from Sysinternals to view the Environment variables on services.exe, it shows the unexpanded version. Coincidentally, the paths using %SystemRoot% expand and are recognized just fine. I've tried altering the PATH through the Environment Variables window from System Properties and through direct Registry manipulation, neither seems to work. Is it possible to use other environment variables, besides %SystemRoot% in PATH and have services.exe understand it?

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• How to solve " dpkg was interrupted, you must manually run 'dpkg --configure -a' to correct the prob

  - by Hoang

  I get this message when my ubuntu system was crashed. How to solve it?

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• Newbie ask Swap Value: How much Swap do I have?

  - by Cintaku

  When looking vmstat, this is what I got: procs -----------memory---------- ---swap-- -----io---- --system-- -----cpu------ r b swpd free buff cache si so bi bo in cs us sy id wa st 1 0 0 2872 0 0 0 0 8 17 0 14 3 1 94 2 0 the cache is 0. I have no idea how much the whole swap I have. But when not enough RAM (256 MB), the swap will be used and look like below: procs -----------memory---------- ---swap-- -----io---- --system-- -----cpu------ r b swpd free buff cache si so bi bo in cs us sy id wa st 3 1 2468 0 0 0 0 0 8 17 0 16 3 1 94 2 0

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