/ - rtt - IT Resource

  • Linux Permissions and Groups Real Usecase for Group Access


    I have a directory structure which the primary user needs full access on but wanted a user to access only a specific directory within the main directory (so they could write in there only and nowhere else). Here's what I did: [root@compevo8001 dllnow]# ls -alh drwxrwxr-x  2 someuser software  4.0K Oct 19  2017 ExpireYMD-2017-11-20 drwxrwxr-x  2 someuser software  4.0K Nov 19  2017 ExpireYMD-20........
  • HP DL385 G7 Linux BIOS Update Flash


    wget https://downloads.linux.hpe.com/repo/spp/rhel/6/x86_64/current/CP017004.scexe --2018-08-16 05:11:16--  https://downloads.linux.hpe.com/repo/spp/rhel/6/x86_64/current/CP017004.scexe Resolving downloads.linux.hpe.com (downloads.linux.hpe.com)... 15.249.152.85 Connecting to downloads.linux.hpe.com (downloads.linux.hpe.com)|15.249.152.85|:443... connected. HTTP request sent, awaiting response... 200 OK Length: 1525561 (1.5........
  • Cannot install moodle


    After starting the install it stalls here: admin/index.php?cache=0&agreelicense=1&confirmrelease=1&lang=en If you manually refresh you get a Plugins check screen: Installation System Moodle second step fails just blank screen: https://domain.la/user/editadvanced.php?id=2 Solution: give up and choose something else it shouldn't be thi........
  • vmkping -I vmk1 10.0.2.69 PING 10.0.2.69 (10.0.2.69): 56 data bytes sendto() failed (Host is down)


    [root@localhost:~] vmkping -I vmk1 10.0.2.69 PING 10.0.2.69 (10.0.2.69): 56 data bytes sendto() failed (Host is down) vsphere distributed switch vmotion not working [root@localhost:~]  esxcfg-route -l VMkernel Routes: Network          Netmask          Gateway          Interface &........
  • h264 DVR security camera footage cannot be played


    This is not just a Linux issue but a general issue most software or hardware players cannot play the resulting exported/backed up format of .h264 from DVR security camera footage for some silly reason. There is a simple solution in Linux using ffmpeg fortunately. Convert the .h264 file into mp4 ffmpeg -i yourfile.h264 -codec copy video.mp4   play dvr .h264 file........
  • imagemagick pdf convert error solution - **** Warning: can't process font stream, loading font by the name. Can't find CMap Identity-UTF16-H building a CIDDecoding resource. Warning: falling back to Identity ordering **** Error reading a conte


       **** Warning: can't process font stream, loading font by the name. Can't find CMap Identity-UTF16-H building a CIDDecoding resource. Warning: falling back to Identity ordering    **** Error reading a content stream. The page may be incomplete.    **** File did not complete the page properly and may be damaged.    **** This file had errors that were repaired or ignored.    ****........
  • Linux Mint missing ffmpeg solution to install from Ubuntu PPA


    This is very annoying that ffmpeg is missing from Linux Mint!  They have ffmpeg2theora which is a totally different codec and does not work as ffmpeg does at all (it is basically totally different). However on Linux Mint 17 I was able to use a Ubuntu PPA and sucessfully install ffmpeg! https://launchpad.net/~mc3man/+archive/ubuntu/trusty-media Adding this PPA to your system........
  • Avocent DSR8020 KVM/IP - Network Connect Error - Solution


    This error is commonly due to Java security or TLS settings but there is a second issue with forwarded ports that also causes it.   1. Java Security/TLS Settings issue: This article has the solution to change them all in Linux automatically 2. Port Forwarding Issue if your Avocent DSR is behind NAT/private IP........
  • Using a proxy with yum in Centos 6


    Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=6&arch=x86_64&repo=os error was 12: Timeout on http://mirrorlist.centos.org/?release=6&arch=x86_64&repo=os: (28, 'Operation too slow. Less than 1 bytes/sec transfered the last 30 seconds') Error: Cannot find a valid baseurl for repo: base You would think this should be fine and simple like using a proxy with most other software? However........
  • How to Normalize and Increase the Volume on M4A files in Linux


    M4A is a weird format, so you have to be creative here is a quick copy of what I did.  Basically you need to convert to .wav to make use of them and then I converted the resulting .wav into an mp3 (nice small file size and basically universally playable):   =======   sudo apt-get install mpg321 mp3gain faad normalize lame  faad "Voice 002 (copy).m4a" faad "Voice 002 (copy).m4a"........
  • ONVIF Linux Security Camera Setup


    First of all this seems to apply to many ONVIF devices Hard coded IP: 192.168.1.10 (yes not kidding no DHCP!) 00:12:12:9C:C2:00 To view RTSP stream use VLC, or openRTSP or other RTSP capable software: rtsp://192.168.1.10/user=admin_password=tlJwpbo6_channel=1_stream=0.sdp user: admin password: blank http://ip/Login.htm Uses Quicktime and is a poor quality picture and slow Cannot change pass........
  • flypro EEPROM PLCC32 programmer software error "The device ID does not match, whether to continue operating"


    If you get that message it means you have inserted the adapter or device incorrectly.  In my case the adapter needed to be at the rear end of the pins and it caused this message. Do not ignore this message as it may appear to work but you will get errors and in reality your chip will not be erased or programmed even if it appears like it is working.........
  • HP Procurve Switch 2824 CLI Telnet Experience , Guide and Tutorial


    telnet 192.168.1.54 ------------------------------------- ProCurve J4903A Switch 2824 Software revision I.10.77 Copyright (C) 1991-2009 Hewlett-Packard Co.  All Rights Reserved.                            RESTRICTED RIGHTS LEGEND  Use, duplication, or disclosure by the Government is subject........
  • CPanel Link to all of the command line options


    <p>CPanel says you can access 98% of the functions through CLI which experienced Unix/Linux admins prefer for simplicity and for scripting.&nbsp; I've never found CPanel easy to use from the admin panel, it seems everything is hard to find and a simple task becomes a series of hunts.</p> <p>So for people like me here's the list: <a href="http://cpanel.net/system-administrators/command-line-scripts/">http://cpanel.net/system-administrators/command-line-scrip........
  • Dell SAS 6/ir Cards are just LSi 1068E cards


    02:00.0 SCSI storage controller: LSI Logic / Symbios Logic SAS1068E PCI-Express Fusion-MPT SAS (rev 08) 03:00.0 SCSI storage controller: LSI Logic / Symbios Logic SAS1068E PCI-Express Fusion-MPT SAS (rev 08) Basically these cards are a stripped-down version of Dell Perc 6/i only  they (SAS 6/ir) support JBOD. The Dell Perc 6/i are basically useless because it doesn't have JBOD support and requires software or BIOS commands to add or remove........
  • LSI MegaRAID Adventures, Guide and HowTo


    LSi Megaraid At first it was configured as a RAID 0, then I deleted the Virtual Disk Group. I thought both drives would be shown and detected in Linux as sda and sdb but it actually shows nothing. To make them work you have to hit Ctrl+R before the system boots (when prompted) and create a Virtual Disk Group.  In my case I created each one as RAID 0 (with a single drive only) as I just wanted JBOD but there is no such option or default in these Dell Pe........
  • SSH Can't Login/Hang


    Client Log OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008 debug1: Reading configuration data /etc/ssh/ssh_config debug1: Applying options for * debug1: Connecting to 192.168.1.253 [192.168.1.253] port 22. debug1: Connection established. debug1: permanently_set_uid: 0/0 debug1: identity file /root/.ssh/identity type -1 debug1: identity file /root/.ssh/id_rsa type 1 debug1: identity file /root/.ssh/id_d........
  • mdadm: /dev/sdb1 not large enough to join array solution


    mdadm --manage /dev/md1 --add /dev/sdb1 mdadm: metadata format 00.90 unknown, ignored. mdadm: metadata format 00.90 unknown, ignored. mdadm: metadata format 00.90 unknown, ignored. mdadm: /dev/sdb1 not large enough to join array md1's first primary member /dev/sda3 has 57394 cylinders while the /dev/sdb1 has 57393 (1 less cylinder) which is why it won't work.  fdisk -l /dev/sda3 Disk /dev/sda3: 47........
  • What's Needed To Fix Linux


    I really am a Linux fan but my comments here may not show it.  Although I'm quite familiar with Linux CLI to administer servers, I find Linux GUI OS's like Ubuntu at times very clunky. This is partially because there's no such thing as a "self-made" Linux from scratch where the UI was designed by a single team.  Linux is made up of several different projects that are generally completely separate and this lack of integratiion is a key issue that makes things f........
  • Linux OCR Comparison


    http://www.splitbrain.org/blog/2010-06/15-linux_ocr_software_comparison They did a great writeup and comparison on the different OCR options available for Linux.........
  • 2011 Best Laptop - HP 15.6" Laptop featuring AMD Athlon II P340 Processor (G62-420CA)


    My mother needed a new laptop and I recommended her the same one I would have bought myself or my wife, that means the cheapest possible laptop with the most features for the money. This HP shines at this price point and one thing that made me stay away from buying more and recommending HP/Compaq was the poor battery life.  Not anymore, this model has an industry leading up to 4 hours of battery life. Key Factors for Choosing It: HDMI Out........
  • OpenOffice Calc SUM function not working Solution - Result is always 0/apostrophe appears in front of all numbers.


    I right clicked all applicable cells and chose "number" but that's enough. I notice when I click the cell there is an invisible ' in front of the number: '33.64 Calc imported my CSV and decided to add a ' in front of the numeric currency values!!!*Actually the problem occurs when you right click the cells and change the type from text to number, no matter what format you choose. If I change it to be currency i........
  • SSH delay problem UseDNS and disabling GSSAPI does not help


    The normal solution doesn't help or apply here:   ssh -v user@192.168.5.41 OpenSSH_4.3p2 Debian-9etch3, OpenSSL 0.9.8c 05 Sep 2006 debug1: Reading configuration data /etc/ssh/ssh_config debug1: Applying options for * debug1: Connecting to 192.168.5.41 [192.168.5.41] port 22. debug1: Connection established. debug1: permanently_set_uid: 0/0 debug1: identity file /root/.ssh/identity type -1 debug1: i........
  • mdadm Linux Software RAID QuickStart Guide


      Create New RAID 1 Array: First setup your partitions (make sure they are exactly the same size) In my example I have sda3 and sdb3 which are 500GB in size. mdadm --create /dev/md2 --level=1 --raid-devices=2 /dev/sda3 /dev/sdb3 mdadm: array /dev/md2 started. Check Status Of The Array *Note I already have other arrays md0 and md1. You can see below that md2 is syn........
  • Ubuntu 10.04 Linux is still not ready for the Desktop world


    I am a huge fan of Linux and the idea of OpenSource but I've said it many times, there are still hurdles in today in 2010 for Linux as a Desktop.  Linux is still intended for servers at its very core.  This can be changed succesfully though, as Apple has shown us with Mac OS X based on FreeBSD. Half of the issue is lack of driver support and the other half is the Linux Kernel and Window Manages, KDE and GNome still both don't cut it (but they're getting closer). I'll........
  • mdadm "auto-read-only" Linux Software RAID solution


    If you have the "(auto-read-only)" beside an array I have no idea why that happens but it is easy to fix. Just run "mdadm --readwrite /dev/md1" (rename md0 to the device with the problem and it will begin to resync.   md1 : active (auto-read-only) raid1 sdb2[0] sda2[1]       19534976 blocks [2/2] [UU]         resync=PENDING      ........
  • mdadm Linux Software RAID auto-detect and assemble RAID Array


    mdadm --assemble --scan mdadm: /dev/md/diaghost05102010:2 has been started with 2 drives. mdadm: /dev/md/diaghost05102010:1 has been started with 2 drives. mdadm: /dev/md/diaghost05102010:0 has been started with 2 drives. -bash-3.1# cat /proc/mdstat Personalities : [linear] [raid0] [raid1] [raid6] [raid5] [raid4] [multipath] md125 : active raid1 sda1[0] sdb1[1]       14658185 blocks super 1.2........
  • tar gzip: stdout: File too large - Error Size Limit on Large file > 17GB


    The folder I was trying to archive is about 72GB, but much like rsync at about 17GB it chokes because of the filesize.  What's with so many common and essential Linux tools having such limitations?  I guess it is likely that the authors never wrote their code with the idea that files would be so large but it's still very annoying.  It's important to stay on top of these limitations on production servers because I didn't realize what happened until I checked the file with "........
  • CentOS (most Linux) no-RAID to software RAID-1 guide


    CentOS (most Linux) no-RAID to software RAID-1 guidehttp://lists.centos.org/pipermail/centos/2006-January/018624.html........
  • Nice General Linux RAID 1 Guide


    Nice General Linux RAID 1 GuideFull examples/tutorials that should work for any Linux system using GRUB or LILO as the boot loader. This is the only tutorial I've seen that clearly shows how you can convert an existing non-RAID system to software RAID1 remotely, without ever having to be at the computer. This is important for people who co-locate or rent dedicated servers that they may not have physical access to in a timely manner. https://alioth.debia........
  • The New Chips on the Block


    The New Chips on the BlockThe New Chips on the Block By Bruce Gain Story location: http://www.wired.com/news/infostructure/0,1377,67795,00.html 02:00 AM Jun. 13, 2005 PT We have embarked upon a new era in x86 PC computing -- so say chip giants AMD and Intel following their launches of dual-core PC processors. So how will dual-core processing change your PC computing experience? Our FAQ should help you decide whether or when you sho........
  • Norton Antivirus is the worst - who would have known?


    Norton Antivirus is the worst - who would have known?http://www.software-antivirus.com/ Check the link above, that review site lists Norton as one of the ones to stay away from. With good reason too, I always wondered why Norton seemed to miss so many viruses, spyware and such. Even when it didn't, it was absolutely useless because it was either unable to delete the file and it was never able to repair or disinfect. So in essence, from my experience, N........
  • My list of handy security links - Ongoing


    My list of handy security links - Ongoing[b:6f8d25be68][size=18:6f8d25be68]News[/size:6f8d25be68][/b:6f8d25be68] Security Focus http://www.securityfocus.net - Nice Security News Site CERT http://www.cert.org/ Common Criteria (see if your OS/software is EAL4 certified) EAL(Evaluation Assurance Levels is the industry standard for evaluation of security in software) http://www.commoncriteria.com [size=18:6f8d25be68][b:6f8d25be68]Tools[........
  • Other Security Web Sites


    Other Security Web SitesSeveral websites actively track security issues. This list provides you with the major providers of security information on the Web. Many of these organizations also provide newsletters and mailings to announce changes or security threats: Center for Education and Research in Information Assurance and Security (CERIAS) CERIAS is an industry-sponsored center at Purdue University that is focused on technology and relate........
  • gnuCash - Alternative to Quickbooks/Quicken and other COTS accounting software.


    gnuCash is available for all main platforms, Linux/Unix, MacOS (FreeBSD anyway), and Windows. You can download gnuCash free from here. It does seem to be fairly full featured and somewhat straight forward, but like so many programs it is missing a few key features or things don't work quite right. It doesn't support importation of CSV files, which is a big minus.  And the developers rather than wanting to add support have just dec........
  • iPhone/iPod touch on 3.0 software overheating?


    There have been lots of reports like this going around and I can confirm my 3GS with 3.0 firmware is overheating as well.  It gets quite hot and actually can make your head or hand sweaty when holding it to talk, or simply holding the back cover for any reason. It's a wonder how the device cools itself at all, considering the only thing that could ventilate air are the 2 speakers at the bottom or the single speaker on the front of the device. Apple seems to be making........
  • Why Apple should thank the jailbreakers and not patch/stop the jailbreaking exploits


    First of all, the iPhone is crippled in many ways, but most of my complaints about functionality have been addressed through the jailbreak, I can run apps in the background of my choosing, I can install a terminal, acccess my phone through SSH and SCP and so much more. It even addresses the 15 minute e-mail problem, I installed a program called "PushMod" and now set the checking time to just 1 minute. Apple should really thank the developers for this gift, it ma........
  • iPhone/iTunes sync error "0xE8008001"


    This happened during a sync of my iPhone while installing some apps.  This usually happens to non-jailbroken iPhones who are trying to install non-Apple approved software OR jailbroken phones who haven't done the "Sync update". How to fix this error and get the Sync Update Open Cydia - Manage - Sources - Edit Add this source: http://cydia.hackulo.us Then under the section "Hackulo.us" install "Ap........
  • iPhone 3GS Jailbreak Information & Benefits


    Truly, the only way to unleash the capabilities and customization abilities of iPhone are to jailbreak, it's not just for hackers anymore. A few days ago someone by the named of "geohot" released a single click application called "purplera1n", which does the entire operation smoothly and seamlessly. In our case, the first time it went as far as "done, wait for reboot" on our Windows machine and for minutes we waited and saw the pic on the iPhone w........
  • iPhone 3GS 32GB "Harsh Review"


    Yes, I admit I finally got bitten by the hype as much as I can usually see through it all.  Keep in mind this review is of the "stock" phone, no jailbreaking yet which is what really unleashes the customizability and why I bought iPhone. I had better things to say about this phone before buying it, and it is a great phone, perhaps the best on the market by far, if not because of the Mac OS port onto the iPhone and all the apps, etc, etc. With that said........
  • Apple iPhone 3GS and predecessors are leading a revolution


    As much of a computer nerd as I am, I'm usually a late adopter to technology for a few reasons.  I feel most new hyped technologies and electronics are mainly fads, and I'm also cheap. Adopting later means you avoid the bugs, kinks and most importantly pay the lowest price, that's me being cheap again :) I never read much about the iPhone but I saw all the hype around it and until recently I wasn't a big fan of anything Apple until a few years ago I realize........
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