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Articles indexed Thursday October 17 2013

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  • Can't connect to EC2 instance in VPC (Amazon AWS)

    - by Ryan Lynch
    I've taken the following steps: Created a VPC (with a single public subnet) Added an EC2 instance to the VPC Allocated an elastic IP Associated the elastic IP with the instance Created a security group and assigned it to the instance Modified the security rules to allow inbound ICMP echo and TCP on port 22 I've done all this and I still can't ping or ssh into the instance. If I follow the same steps minus the VPC bits I am able to set this up without issue. What step am I missing?

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  • High disk I/O - jbd2/sda2-8 process

    - by Evan Hamlet
    I have run a file server on a CentOS 5.8 final server. My only concern at the moment is what appears to be intermittent but continuous high disk I/O activity causing a general slowdown because of jbd2/sda2-8 process. jbd2/sda2-8 is making use of /dev/sda2, which is the 2nd partition of the first harddrive (IE: root partition). More info: using "iotop" the culprit appears to be "jbd2/sda1-8" making writes every second, which appears to be a kernel process associated with journaling on the ext4 filesystem, if my googling around is correct. I see "jbd2/sda2-8" appearing here every now and then, but certainly not every 3 seconds.. when idle, it appears about 1 or 2 times per minute. When I'm using the system, it appears more frequently. ATOP results: http://grabilla.com/02b14-8022db2e-4eb9-4f10-8e10-d65c49ad7530.png IOTOP results: http://grabilla.com/02b14-cf74b25d-4063-4447-9210-7d1b9b70e25b.png HTOP results: grabilla. com/02b14-ad8cad0e-89b0-46d3-849d-4fd515c1e690.png jbd2/sda2-8 is the processes I see with iotop making writes on disk even though it's not in use at all. Does someone has any idea how could I solve the high disk usage caused jbd2/sda2-8 process?

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  • Exchange 2010 PST-Export fails

    - by Chake
    I'm horribly failing at exporting Exchnange Mailboxes to PST files. Perhaps You are able to help me? The System I'm running some legacy machines here. The one I'm currently working on (CurrentDC) is a Windows 2008 R2 Server with Exchange 2010 on it. Exchange seems to be poorly patched: [PS] C:\>get-exchangeserver Name Site ServerRole Edition AdminDisplayVersion ---- ---- ---------- ------- ------------------- OldDC None Enterprise Version 6.5 (Bui... CurrentDC company.local Mailbox,... Enterprise Version 14.0 (Bu... The Problem After some trouble I managed to get the Export-Mailbox command run: [PS] C:\>Export-Mailbox -Identity marco -PSTFolderPath C:\ExchangeExport According to several Websites that seems to be the right command to export the mailbox of the user "marco" to "C:\ExchangeExport". But after running the command an error occurs (I'm sorry, it is the german version of Windows 2008 - but if you translate Fehler with error and Vorgang with process you should be prepared enough to go ;)) [PS] C:\Export-Mailbox -Identity marco -PSTFolderPath C:\ExchangeExport Fehler für Marco S ([email protected]). Ursache: Fehler bei diesem Vorgang., Fehlercode: -2147467259. + CategoryInfo : InvalidOperation: (0:Int32) [Export-Mailbox], RecipientTaskException + FullyQualifiedErrorId : 2317FD3A,Microsoft.Exchange.Management.RecipientTasks.ExportMailbox RunspaceId : 44415363-371e-44a1-a682-61e6a9b90c86 Identity : company.local/Company User/Marco S DistinguishedName : CN=Marco S,OU=Company User,DC=company,DC=local DisplayName : Marco S Alias : marco LegacyExchangeDN : /o=Erste Organisation/ou=Erste administrative Gruppe/cn=Recipients/cn=marco PrimarySmtpAddress : [email protected] SourceServer : CurrentDC.company.local SourceDatabase : Mailbox Database 0279110169 SourceGlobalCatalog : CurrentDC SourceDomainController : TargetGlobalCatalog : CurrentDC TargetDomainController : TargetMailbox : TargetServer : TargetDatabase : MailboxSize : 0 B (0 bytes) IsResourceMailbox : False SIDUsedInMatch : SMTPProxies : SourceManager : SourceDirectReports : SourcePublicDelegates : SourcePublicDelegatesBL : SourceAltRecipient : SourceAltRecipientBL : SourceDeliverAndRedirect : MatchedTargetNTAccountDN : IsMatchedNTAccountMailboxEnabled : MatchedContactsDNList : TargetNTAccountDNToCreate : TargetManager : TargetDirectReports : TargetPublicDelegates : TargetPublicDelegatesBL : TargetAltRecipient : TargetAltRecipientBL : TargetDeliverAndRedirect : Options : Default SourceForestCredential : TargetForestCredential : TargetFolder : PSTFilePath : C:\ExchangeExport\marco.pst RecoveryMailboxGuid : RecoveryMailboxLegacyExchangeDN : RecoveryMailboxDisplayName : RecoveryDatabaseGuid : StandardMessagesDeleted : 0 AssociatedMessagesDeleted : 0 DumpsterMessagesDeleted : 0 MoveType : ExportToPST MoveStage : Validation StartTime : 05.10.2012 13:55:46 EndTime : 05.10.2012 13:55:46 StatusCode : -2147467259 StatusMessage : Fehler bei diesem Vorgang. ReportFile : C:\Program Files\Microsoft\Exchange Server\V14\Logging\MigrationLogs\export-Mailbox20121005-135545-8170000.xml ServerName : CurrentDC.company.local What I have done Well, I must say I'm quite clueless. I was wondering why MailboxSize is 0 - so I checked it: [PS] C:\>Get-MailboxStatistics marco | ft DisplayName, TotalItemSize, ItemCount DisplayName TotalItemSize ItemCount ----------- ------------- --------- Marco S 473 MB (496,011,572 bytes) 4173 Well, this i not 0 bytes - but I don't know what to do with this information. Also I had a look at the ReportFile mentioned in the output: <?xml version="1.0"?> <export-Mailbox> <TaskHeader> <RunningAs>NT-AUTORITÄT\SYSTEM</RunningAs> <Name>export-Mailbox</Name> <Type>ExportToPST</Type> <MaxBadItems>0</MaxBadItems> <Version>14.0.639.21</Version> <StartTime>10.05.2012 14:19:12</StartTime> <Options Identity="marco" PSTFolderPath="C:\ExchangeExport" DeleteContent="False" DeleteAssociatedMessages="False" GlobalCatalog="CurrentDC" MaxThreads="4" BadItemLimit="0" ValidateOnly="False" IncludeFolders="" ExcludeFolders="" StartDate="01.01.0001 00:00:00" EndDate="31.12.9999 23:59:59" SubjectKeywords="" ContentKeywords="" AllContentKeywords="" AttachmentFilenames="" SenderKeywords="" RecipientKeywords="" Locale="" /> </TaskHeader> <TaskDetails> <Item MailboxName="Marco S"> <Source> <Identity>company.local/Company User/Marco S</Identity> <DistinguishName>CN=Marco Sc,OU=Company User,DC=company,DC=local</DistinguishName> <DisplayName>Marco S</DisplayName> <Alias>marco</Alias> <LegacyExchangeDN>/o=Erste Organisation/ou=Erste administrative Gruppe/cn=Recipients/cn=marco</LegacyExchangeDN> <PrimarySmtpAddress>[email protected]</PrimarySmtpAddress> <SourceServer>CurrentDC.company.local</SourceServer> <SourceDatabase>Mailbox Database 0279110169</SourceDatabase> <IsResourceMailbox>False</IsResourceMailbox> <SourceGlobalCatalog>CurrentDC</SourceGlobalCatalog> </Source> <Target> <PSTFilePath>C:\ExchangeExport\marco.pst</PSTFilePath> </Target> <MailboxSize>0 B (0 bytes)</MailboxSize> <Duration>00:00:00</Duration> <Result IsWarning="False" ErrorCode="-2147467259">Fehler bei diesem Vorgang.</Result> </Item> </TaskDetails> <TaskFooter> <EndTime>10.05.2012 14:19:13</EndTime> <TotalSize>0 B (0 bytes)</TotalSize> <StandardMessagesDeleted>0</StandardMessagesDeleted> <AssociatedMessagesDeleted>0</AssociatedMessagesDeleted> <DumpsterMessagesDeleted>0</DumpsterMessagesDeleted> <Result ErrorCount="1" CompletedCount="0" WarningCount="0" /> </TaskFooter> </export-Mailbox> Do you have any clue? <UPDATE> Regarding to the answer from downthepub I tried to use UNC paths - no change. Also I tried installing the management tools to a client and run the scripts from there - no way, too. </UPDATE> Thanks a lot for reading this mess!

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  • How can I prevent a DDOS attack on Amazon EC2?

    - by cwd
    One of the servers I use is hosted on the Amazon EC2 cloud. Every few months we appear to have a DDOS attack on this sever. This slows the server down incredibly. After around 30 minutes, and sometimes a reboot later, everything is back to normal. Amazon has security groups and firewall, but what else should I have in place on an EC2 server to mitigate or prevent an attack? From similar questions I've learned: Limit the rate of requests/minute (or seconds) from a particular IP address via something like IP tables (or maybe UFW?) Have enough resources to survive such an attack - or - Possibly build the web application so it is elastic / has an elastic load balancer and can quickly scale up to meet such a high demand) If using mySql, set up mySql connections so that they run sequentially so that slow queries won't bog down the system What else am I missing? I would love information about specific tools and configuration options (again, using Linux here), and/or anything that is specific to Amazon EC2. ps: Notes about monitoring for DDOS would also be welcomed - perhaps with nagios? ;)

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  • Reverse proxy with SSL and IP passthrough?

    - by Paul
    Turns out that the IP of a much-needed new website is blocked from inside our organization's network for reasons that will take weeks to fix. In the meantime, could we set up a reverse proxy on an Internet-based server which will forward SSL traffic and perhaps client IPs to the external site? Load will be light. No need to terminate SSL on the proxy. We may be able to poison DNS so original URL can work. How do I learn if I need URL rewriting? Squid/apache/nginx/something else? Setup would be fastest on Win 2000, but other OSes are OK if that would help. Simple and quick are good since it's a temporary solution. Thanks for your thoughts!

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  • compressing dd backup on the fly

    - by Phil
    Maybe this will sound like dumb question but the way i'm trying to do it doesn't work. I'm on livecd, drive is unmounted, etc. When i do backup this way sudo dd if=/dev/sda2 of=/media/disk/sda2-backup-10august09.ext3 bs=64k ...normally it would work but i don't have enough space on external hd i'm copying to (it ALMOST fits into it). So I wanted to compress this way sudo dd if=/dev/sda2 | gzip > /media/disk/sda2-backup-10august09.gz ...but i got permissions denied. I don't understand.

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  • URI Scheme, launch program in its directory

    - by ZaKlaus
    I have registered URI scheme for my app. When I open it with "Run.." or in browser, it runs in hosted directory. For ex. Ive opened url in webpage, program's working dir is in browser. What I want? I want to run program test.exe located at C:\data\test.exe and to use dir. C:\data so it could use other data in relative path. so test.exe would access file .\file.txt without using absolute path Hope I wrote it understandable, sorry for bad English.

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  • Cumulative average using data from multiple rows in an excel table

    - by Aaron E
    I am trying to calculate a cumulative average column on a table I'm making in excel. I use the totals row for the ending cumulative average, but I would like to add a column that gives a cumulative average for each row up to that point. So, if I have 3 rows I want each row to have a column giving the average up to that row and then the ending cumulative average in the totals row. Right now I can't figure this out because I'd be having to reference in a formula rows above and below the current row and I'm unsure about how to go about it because it's a table and not just cells. If it was just cells then I know how to do the formula and copy it down each row, but being that the formula I need depends on whether or not a new row in the table is added or not I keep thinking that my formula would be something like: (Completion rate row 1/n) where n is the number of rows up to that point, here row 1, then ((Completion rate row 1 + Completion rate row 2)/n) for row 2 so n=2, and so on for each new row added. Please advise.

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  • Windows 8.1 fresh install with Windows 8 licence

    - by typ1232
    I purchased Windows 8 online from Microsoft a while ago. Today Windows 8.1 was released as a free update to Windows 8 users over the Windows Store. I was planning to do a fresh install of Windows 8.1 to have a clean system again and UEFI support because I got new hardware since the Windows 8 installation. So my questions are: Where do I get the ISO installation medium for Windows 8.1 64-bit? I tried this microsoft site where I initially got my Windows 8 ISO from, but when entering my Windows 8 key in the Windows 8.1 installer, it says the key is wrong. Even if I get the ISO, will my old key work? I'm concerned because it didn't work in their installer (see previous point) Do they seriously want me to reinstall Windows 8 and after that upgrade to Windows 8.1 through their Store?!

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  • How do I know if I need to backup locally stored emails?

    - by Sometimes
    I am moving a friend's website and emails from the current server to a new one. I don't have much experience working with migrating emails and in the past when moving servers all the emails have disappeared from the users local inbox, eg. MS Outlook. To make my question more clear, How do I know if I have to backup the emails before moving server? as I know sometimes they are stored locally and sometimes they are not. And, how do I know if the emails will remain on the user's machine once I move the information from server to server?

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  • Is it possible to update from Windows 8 Enterprise to version 8.1 without having to reinstall the OS?

    - by foregon
    Today we are told that the 8.1 update, (a version which allows you to keep apps, settings, and files), is officially being rolled out worldwide. No longer will you have to do a clean OS install, to go from 8 to 8.1. But I don't see the update inside my (Enterprise's) desktop 'Windows Update' program, and furthermore, Microsoft themselves say: If you’re running [Enterprise], you can't install the free update to Windows 8.1 or Windows RT 8.1 from the Store. However they DO also say: If you installed Windows 8 using an MSDN ISO, you might be able to install Windows 8.1 using a similar ISO from MSDN But it does not specify whether this method allows seamless apps and settings-retaining upgrading or not. Is there a method for doing it (whether official or unofficial - perhaps confirmed via experience of updating with some sort of Enterprise 8.1 ISO), or is an update indeed expected for the Enterprise version via the desktop 'Windows Update' program? A further observation which may help: the page I cite refers to the 'Windows Store', which is the 'Modern UI' app store and NOT the desktop 'Windows Update' program which typically updates desktop Office and desktop Windows alike.

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  • Change Command Prompt width from the Command Line

    - by Starkers
    Don't really know what more I can say really. That window captured below will simply not get any larger. Are there some settings somewhere that will allow me to resize it? See, this limited window thing has left me in a bit of a pickle. Basically I've created an application with a command line GUI (With Ruby's Curses Library), and while everything works beautifully on OSX and Ubuntu Terminals, with Command Prompt, if the Curses Windows are larger than the Command Prompt window as shown below, the whole application crashes with a 'window already closed' error. So, is there a setting that allows users to resize their Command Prompt window, something that I'll have to put in the documentation. Here's what the holy grail answer would, be though: Is there a way to do this from the command line? Could my application detect if the Command Prompt it's running on is of fixed width, and actually programatically run the command to allow the Command Prompt window to be enlarged? Or at least give the user a helpful error message?

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  • Problems when pasting Outlook 2010 signature logo into message body

    - by Austin ''Danger'' Powers
    Whenever I paste my company logo into a message in Outlook 2010, I run into a variety of complications and anomalies. The dimensions of my original logo image are 315x174 (source image is a PNG file). I am scaling this image down in Photoshop CS6 to a variety of smaller sizes for testing my Outlook signature (300x166, 250x138, 200x110,150x83 and 100x55 pixels). 300x166 = no distortion. This looks the same as in Photoshop (but far too large to use in my signature). 250x130 = distorted (gets stretched much wider by Outlook when pasting into message body). 200x110 = looks reasonable, but seems to have been scaled to a different size (smaller) by Outlook for no obvious reason. 150x83 = for some reason, this is scaled by Outlook to the exact same size that 200x110 was scaled to. In fact, a large range of similar dimensions are scaled to the exact same image size by Outlook. This is very frustrating. Why is this happening and what can be done to prevent it? 100x55 = when pasting my logo from Photoshop to Outlook with these dimensions all that happens is the cursor jumps forwards about an inch on the screen, leaving a blank space where the image was supposed to go. Any advice would be much appreciated.

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  • Script/ Macro in Excel, by clicking on a cell

    - by Noob Doob
    There's something I want to do in Excel 2010. Specifically, I want to be able to make the open sheet load data from a text file, by clicking -important- on a cell of the current open worksheet. So my specific needs are: If it is possible in some way, to start a macro/script by clicking on a cell. About the script/macro: What would be the preferable, by your opinion, way of implementation. And more specifically, how to automatically import the data needed, only by clicking, without having to continually specify the desirable .txt file each time, only 1 time at max, at start or by using a custom "initalization/configuration" file.

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  • run a 2nd computer as an extra processor

    - by MMK
    I have a laptop with a busted l.c.d., but otherwise works fine with an external monitor. I was wondering if it is possible to connect it to my main pc as an extra processor(main pc is getting old, it's only single core processor) and if so how? I currently have them connected with a network cable so that I can access the laptop's hard drive but would like to use it to give my pc a bit more power. Both my pc and my laptop have 2 gb ram and are running windows vista sp2

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  • ubuntu package dependency error

    - by Sabareesh Kkanan
    Webmin was upgrading packages and something went wrong after that and now i cannot install anything. Even my apache server is down . When i type apt-get install apache2 i get this error The following packages have unmet dependencies: apache2 : Depends: apache2-mpm-worker (= 2.2.22-6ubuntu2.3) but it is not going to be installed or apache2-mpm-prefork (= 2.2.22-6ubuntu2.3) but it is not going to be installed or apache2-mpm-event (= 2.2.22-6ubuntu2.3) but it is not going to be installed or apache2-mpm-itk (= 2.2.22-6ubuntu2.3) but it is not going to be installed Depends: apache2.2-common (= 2.2.22-6ubuntu2.3) but it is not going to be installed E: Unable to correct problems, you have held broken packages. then i ran apt-get dist-upgrade and got this The following packages have been kept back: libtiff4 libxml2 rpm-common 0 upgraded, 0 newly installed, 0 to remove and 3 not upgraded. please help

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  • AMD switchable graphics are not working OR I don't know how to make them work

    - by Deus Deceit
    I don't know if this is the right place for this question, but I'll give it a shot. I have a Dell Inspiron 17R 5721. It's supposed to be using switchable graphics. It has an Intel HD 4000 and a Radeon HD 8730M and I'm using windows 8. My problem is this, I Installed the drivers that dell gives me but I don't see the AMD graphics card ANYWHERE ( I do see it in device manager but not anywhere else to select and play a game using AMD). I installed the latest drivers from AMD and same thing, I can't run a game with AMD graphics card. I change the applications preferences in the Catalyst control center but even after that, games don't give me the option to select the AMD card, they list only the Intel HD 4000. Can someone tell me what I have to do to make this work? ------------------- After looking around and messing with stuff. I think.... I THINK that you don't really get the option to select a graphics card. Switchable graphics is all about switching automatically depending on application's needs. Cause when I uninstalled AMD's drivers or actually (screwed up lol) games were playing much worse. When I re-installed them, games went back to being good looking. So even if a game sees only the Intel HD 4000 graphics card windows or AMD's drivers will switch to the AMD Readeon graphics card automatically. I hope someone can verify this. Cause seriously I don't think you get to play scyrim with High graphics settings or even ultra with the Intel HD Graphics card. -------------------

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  • What's the utility of the return command in autohotkey?

    - by Shashank Sawant
    In the instances where the return command returns a value, the utility is obvious. I have seen the return command being used even when it is seemingly unnecessary. Let me show the following examples: Example 1: Loop { if a_index > 25 break ; Terminate the loop if a_index < 20 continue ; Skip the below and start a new iteration MsgBox, a_index = %a_index% ; This will display only the numbers 20 through 25 } Example 2: IfWinExist, Untitled - Notepad { WinActivate ; Automatically uses the window found above. return } Why is the return command used in Example 2 but is not used in Example 1? Both examples are copy-pasted/modified-pasted from the autohotkey.com's documentation.

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  • One Way Sync with Dropbox?

    - by user244805
    Is there any way I can mirror a dropbox folder to my C drive by just running a portable file? Extra background information because I know you guys hate it when you don't get the entire situation: I go back to University in fall and I need a new storage solution. I decided to use DropBox to sync my tiny University files (< 5 MB). I need to access these files from 4 machines: Windows 7 Home machine Windows 7 University A machine Windows 7 University B machine Android tablet 1 and 4 are a non-issue. The problem lies with 2 and 3. I want to be able to edit my files on 2 and 3 but those machines are not mine. There is an easy fix. Run a portable version of the DropBox syncer on a USB drive. But the problem is that I don't want to carry a USB drive around with me all the time. In that case, I can just run the small portable DropBox syncer off the internet. But where will it to store the files? A temporary directory on the C drive. There is only one issue left: there are hundreds of machines that I will randomly use that fit in categories 2 and 3. My portable DropBox syncer will notice that the temporary directory is empty on each new PC I use and instead of downloading my DropBox folder to the machine, it syncs the other way around i.e. it deletes my entire DropBox. The solution is to mirror my DropBox onto the temporary directory before running the DropBox syncer.

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  • Outlook won't re-connect to exchange after network is re-connected

    - by stan503
    I have a setup at my desk where I connect my computer to a an RJ45 switch that switches between two networks. One network is the corporate network, which is maintained by my company's IT, and the other is my own private network where I do testing (the two networks have to be separated). The corporate network hosts the exchange server where I get e-mail. When I switch from the private network to the corporate network, I expect Outlook to re-connect to the exchange server. However, I have found that sometimes when I come back, Outlook take an extremely long time to re-connect. Send/Receive will give me back the error 'The server is not available' (0x8004011D). It will sit there for 10 minutes to a few hours before it finally re-connects. The only other option is to reboot my computer, which is a huge pain for me since I run multiple VMs on it. This usually happens when I'm connected to the private network for a significant amount of time, so I'm thinking it's because Outlook has cached the network status. Is there a way to force Outlook to do a 'hard' re-connect to the exchange server? I'm using Windows XP SP 3 with Outlook 2007.

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  • Efficient PuTTy workflow / configuration

    - by Adrian Ratnapala
    PuTTy is a fine SSH client, but how do you get a workflow managed as slickly as OpenSSH on Unix? My issues with PuTTy's management are: PuTTy tools are not in my PATH (easily fixable) PuTTy seems to have no equivalent of ~/.ssh, so I end have to manually choose locations for my keypairs, and then manually tell all the tools where to find them every time The private key's read permissions seem lax (I might be wrong about this, I a klutz on Windows). Pageant doesn't run by default (easily fixable?) Other programs don't reliably find pageant I suspect all of these problems can be fixed if I just get set my system up properly, and/or organise a nice workflow that fits into PuTTy's way of doing things. So can anyone share some success stories about managing PuTTy?

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  • anonymous access to ftpd

    - by gcb
    I need FTP on my local LAN so my scanner can send me scans. I am on Debian sid. I installed ftpd and created the user anonymous. I removed anonymous from /etc/ftpusers When I try to login as anonymous it says: login failed. I can't seem to find any log file. I'm using FTP server (Version 6.4/OpenBSD/Linux-ftpd-0.17) update:I needed that so my printer had one place to store my scanned documents on the LAN. solved that buying a dedicated USB pen drive (thankfully I bought a printer one with plenty of options) but in the past this was a very simple task. Install ftpd, specify the directory for anonymous access, and be done with it. now every ftp daemon has several layers of security and chroot in it's core... this is just crazy when all you need a place for a printer to dump files in a secured network.

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  • In your ssh config is it possible to have one host entry for multiple machines on the same domain

    - by Joshua Olson
    I'd like to be able to do something like Host * HostName *.mydomain.com ... So I can type something like ssh test ssh ci ssh dev Instead of having to type ssh test.mydomain.com ssh ci.mydomain.com ssh dev.mydomain.com Right now I have separate entries for each one, but we have dozens of machines, so I'd rather have a default rather than have to duplicate everything so many times.

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  • Git multiple config files

    - by tig
    As it is told in git-config manual, I have three files to specify git repo configuration: $GIT_DIR/config, ~/.gitconfig and $(prefix)/etc/gitconfig. Is it possible to make git read another config file (for example .gitconfig in root of the repo) after reading $GIT_DIR/config? I want it as I created git command aliases in .git/config and I would prefer to store them in repo, so I can restore them when cloning and for example.

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  • Sleep – Why We Need It and What Happens Without It

    - by Akemi Iwaya
    We spend approximately one-third of our lives sleeping, but why do our bodies need sleep? What is happening in our brains and bodies during our awake and sleeping periods? Could we get by with little to no sleep? Learn the answers to these questions and more with SciShow’s information-packed video about sleep! Sleep: Why We Need It and What Happens Without It [YouTube]     

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