• Linux Ubuntu Debian Missing privilege separation directory: /var/run/sshd


    service sshd status ● ssh.service - OpenBSD Secure Shell server Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled) Active: failed (Result: start-limit-hit) since Wed 2019-10-02 11:07:54 EDT; 36s ago Process: 476 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=255) Oct 02 11:07:54 box systemd[1]: Failed to start OpenBSD Secure Shell server. Oct 02 11:07:54 box sys........
  • Virtualbox vbox not starting


    If you've just installed VBox and it is not starting or working, the most common problem is usually that you don't have your kernel source installed, which means there is no kernel driver for vbox so it can't work. So the first thing you should do is install your kernel source by running this: sudo apt-get install linux-headers-`uname -r` Then install the dkms/kernel module for vbox........
  • Ubuntu Debian Mint Linux SSHD OpenSSH Server Not Starting After Reboot Solution


    If you get error messages like this it is usually because /var/run/sshd does not exist. root@userbox:/# service sshd status ● ssh.service - OpenBSD Secure Shell server Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enab Active: failed (Result: start-limit-hit) since Wed 2019-04-10 02:24:44 EDT; 1 Process: 511 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=255)........
  • How To Boot Cisco CUCM UCSInstall 8.6, 10, 11 and 12 on KVM/Proxmox


    The key thing is that you must use a "machine"id of "pc-1.3" or it will say your hardware is not supported. Additionally you MUST use a virtio disk or you will get a ks_pre.sh error as soon as the install starts (a look at logs will show it can't find a disk). This is funny because even though the OS finds the disk and an fdisk -l shows it, it looks like the script looks for a /dev/vda device (virtio) and nothing else, so if you didn't use Virtio as you........
  • Centos 7 Reallocate logical volume space to another


    Do you hate how Centos 7 defaults to allocating most of your valuable space to /home even though it is a production server? Here is a quick guide on how to take back that space live, while online (of course make sure you have backups just in case something goes wrong!): First we will reduce our home dir by 100G: lvreduce -L -100G /dev/mapper/centos-home WARNING: Reducing active and open logical volume to ........
  • iSCSI on Centos 7 Configuration and Setup Guide for Initiator and Target


    initiator = client target = server These are the first concepts you should understand which is that in iscsi essentially the "initiator" is the client and the "target" is the server. iSCSI is derived from the old fashioned SCSI that us oldtimers grew to love. The "i" stands for Internet and the SCSI stands for "Small Computers Systems Interface" (SCSI). iSCSI Target (Server)Setup targetcli is the pac........
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    This takes "yourvariable" and splits it based on the last character in this case "-" and shows the last field of that split. ${yourvariable##*-} ........
  • How Does Cisco CUCM (Cisco Unified Communication Manager) Work?


    Cisco's CUCM (Cisco Unified Communication Manager) is a system that combines voice, video, data and mobile products into a single unified management suite. At its core, the CUCMis like a "Super PBX" that controls the flow of all communications through an organization even single or multiple site deployments. Cisco's CUCMmakes communication more effective and simple through centralized management and unification of communications resources.........
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    code { background: #f4f4f4; border: 1px solid #ddd; border-left: 3px solid #f36d33; color: #666; page-break-inside: avoid; font-family: monospace; font-size: 15px; line-height: 1.6; margin-bottom: 1.6em; max-width: 100%; &nb........
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  • PHP Displaying Blank Page on Apache


    Almost always the reason will be that the php.so file is missing but also that php.conf is misconfigured. In the problem machine it is actually PHP7 installed so if you reference PHP5 of course things wil be broken! Take for example here: cat /etc/httpd/conf.d/php.conf # # PHP is an HTML-embedded scripting language which attempts to make it # easy for developers to write dynamica........
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    [root@localhost:~] BootModuleConfig.sh echo host-ind nfcd........
  • Hard Drive Serial Number Examples


    The reason for this article is because a lot of us don't physically see our hard drives they are often remote in a datacenter etc and the actual serial number we see in SMART is not enough to check for some manufacturers. A good example is our first one the Toshiba === START OF INFORMATION SECTION === Device Model: TOSHIBA DT01ACA200 Serial Number: 33FMDW4AS........
  • IcedTea Java Web Viewer Config Utility How To Enter


    In at least Ubuntu and Mint there is nothing intuitive about configuring Java. Execute it to get to it: itweb-settings You'll be able to configure different options and variables. You can also check under Security as some of those settings could prevent applets from starting or prompting to........
  • Linux input/output error invalid program cannot read data on some CD-Rs and DVD-Rs on ASUS BW-16D1HT


    I've never seen this before in all of my years. Ihave some very old CDs and DVDs 12-15 years old that seem not to work in this BD-R/DVD-R/CD-R Asus drive. The discs are fine actually and ironically they even work fine on a normal LG USB based BD-R drive! Here are the errors in Linux: [2914936.884924] attempt to access beyond end of device [2914936.884927] loop1: rw=0, want=730424, limit=688384 [2914954.556873] attempt to........
  • 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........
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    add this style="background-size: contain;max-width: 100%; height: auto;" to your img code. Example: ........
  • M2Crypto.SSL.Checker.WrongHost: Peer certificate subjectAltName does not match host, expected fedora-archive.ip-connect.vn.ua, got DNS:mirror.ip-connect.vn.ua


    You are using Centos 5 which is deprecated so nothing in yum will work until you follow this post to use the vault: http://realtechtalk.com/Centos_59_Working_Vault_Repo_file-1921-articles yum update Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * epel: fedora-archive.ip-connect.vn.ua Traceback........
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    myisamchk can fix it But be careful and use the right options to avoid losing data. In fact if you haven't you should make a backup or at least manually copy /var/lib/mysql. Replace "YourDB" with the name of your database Replace "yourcrashedtable" with the name of your crashed table. The -o option is the safest and should avoid dataloss whereas -r is more aggressive and is a last option (I have lost data using -r and........
  • bash Linux how to get first or last letters of a word


    To get the first X letters of a word: It's very simple you can just pipe it to head with -c 1 (gives the first letter and so on) -c2 (2 gives the first 2 letters). echo "dsjfsdlksjdklf;jlsd;kflasdj;kl"|head -c 2 Returns ds To get the last X letters of a word: Now we use tail with -c but it works differently. ........
  • ffmpeg trouble concatenating similar but different files


    When things go wrong your video is basically unplayable or the first video plays fine and then freezes when moving on to the next. Generally if both videos weren't produced with the exact 100% same settings you will have issues. You can try the basic concat but it often won't work right. Solution for me: My example uses 3 videos in total so "n=3" and a=1 to include audio. ffmpeg -threads 12 -i file1.mp4 -........
  • ffmpeg Unable to Use Hardware Encoding with Nvidia 3.40 Driver and GT210 card


    I believe from what I've read that this card's driver doesn't support the features after trying all known troubleshooting methods. ffmpeg -i uservideoRendered.mp4 -filter:v hwupload_cuda,scale_npp=w=1920:h=1080:format=nv12:interp_algo=lanczos,hwdownload -c:v hevc_nvenc -profile main -preset slow -rc vbr_hq -c:a copy uservideoRendered.mp4-test ffmpeg -i uservideoRendered.mp4 -filter:v hwupload_cuda,scale_npp=w=1920:h=1080:format=nv12:interp_algo=lanczos,hwdownload........
  • ffmpeg Linux Mint download, compile and install howto


    #if you have nvidia make sure you install the nvidia-cuda-toolkit so hardware acceleration can be used wget http://ffmpeg.org/releases/ffmpeg-3.3.2.tar.bz2 tar -jxvf ffmpeg-3.3.2.tar.bz2 cd ffmpeg-3.3.2/ ./configure --disable-yasm install prefix /usr/local source path ........
  • Linux how to copy GPT partition table with dd


    The old MBR 512 bytes partition table is no longer valid if you are using GPT. To copy a GPT table with dd to another disk do it like so: Below sda is the source disk and destination disk is sdb (change to meet your needs). dd if=/dev/sda of=/dev/sdb bs=1536 count=1 You can also use dd to backup your partition table like normal but with the bs of 1536 dd........
  • How to change reserved blocks in Linux partition


    user@box:~$ sudo tune2fs -l /dev/md99 [sudo] password for user: tune2fs 1.42.9 (4-Feb-2014) Filesystem volume name: Last mounted on: /mnt/md50 Filesystem UUID: 976a8655-2619-4587-878c-dab07f7b7652 Filesystem magic number: 0xEF53 Filesystem revision #: 1 (dynamic) Fi........
  • USB 3.0 External HDD Enclosure Seagate UAS problems - [sdd] tag#1 CDB: Write(16) 8a 00 00 00 00 01 70 04 08 68 00 00 00 08 00 00


    This is a 8TB Seagate external USB 3.0 device apparently newer kernels use a module called "UAS" instead of "USB Storage" which causes issues as a lot of devices are not properly supported in UAS mode by the kernel driver. The solution some say is to disable UAS specifically for your USB device but I'd rather just disable UAS altogether. Solution blacklist UAS: *do not do this it does not work and just causes your USB 3.0........
  • USB 3.0 PCI x1 Card Review VIA VL805 on Linux Review and Experience


    This is a VIA made VL805 USB 3.0 Chipset with 4-ports and MOLEX powered. First of all this unit was cheap at about only 9 USD with fast shipping. My biggest concern was if this was a quality unit and would it really give you full USB 3.0 speeds (some people reported with similar cards that for some weird r........
  • rsync run as root sudo without password


    This is a common issue, what if a issue shouldn't have root but you want to use that user to make a full backup of a system? They of course need root access. You can actually just give them passwordless sudo access to rsync in /etc/sudoers: sudo vi /etc/sudoers yourusername ALL = NOPASSWD: /usr/bin/rsync Here is how you would execute rsync: The key thing for the remote host is to........
  • Centos/Linux Bash Script Warning when exiting/logging out of bash/shell/terminal for scripts running in the background


    This is mainly the case on Centos but applies to other distros and situations. If you are running programs in the background with the &, at least in Centos it is usually not honored and if you quit or are disconnected the backgrounded programs will be sent sighup and be shut down. The simplest way around this instead of using & is to start any programs or commands with "nohup" Eg. nohup yourscript.sh........
  • Openshot 2.2 is very unstable always crashing in Linux Mint 18.1!


    Jun 1 15:45:42 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: project_data:INFO Missing folder chosen by user: Jun 1 15:45:42 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: project_data:INFO Removed missing file: MAH02949.MP4 Jun 1 15:45:57 videoeditor-desktop org.mate.panel.applet.MintMenuAppletFactory[1882]: ui_util:WARNING Icon theme media-playback-start not found. Will use backup........
  • Track 01: 34 of 1726 MB written (fifo 100%) [buf 99%] 3.6x.Errno: 5 (Input/output error), write_g1 scsi sendcmd: cmd timeout after 1.897 (40) s CDB: 2A 00 00 00 44 A9 00 00 1F 00 resid: 6144 cmd finished after 1.897s timeout 40s write track da


    These errors believe it or not are simply because of not being the root user or running with sudo! However if you didn't know to try as root you'd think there was a problem with your burner or disc Essentially it looks like without root you cannot send the required scsi commands to continue writing. Ithink cdrecord should have built-in tests or safeguards to see if it has the permissions to run the required commands. I guess for more advanced users the idea is simila........
  • mencoder bmovl error vf_bmovl: Unknown command: ''. Ignoring.


    Based on this tutorial: http://www.linuxjournal.com/content/overlay-images-video-using-mplayer-and-mencoder mencoder -oac pcm -ovc raw -vf bmovl=0:0:tfifo -o $output $file vf_bmovl: Unknown command: ''. Ignoring. ........
  • 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........
  • How to Execute PHP in .html files with Apache in Linux Centos/Debian/Ubuntu etc


    Add this to the .htaccess file #right/working: AddType application/x-httpd-php .html .htm #wrong (won't work in many cases): AddHandler application/x-httpd-php5 .html .htm........
  • mdadm and lvm how to completely disable and remove vg/pv/lv


    In short the solution is just to use vgremove for the actual /dev/mapper device: vgremove /dev/mapper/backups-backuplv box mnt # mdadm --manage /dev/md8 --stop mdadm: Cannot get exclusive access to /dev/md8:Perhaps a running process, mounted filesystem or active volume group? box mnt # lv lvchange lvconvert lvcreate l........
  • mdadm mirrored RAID1 performance using RAID10 -f2 (Far Layout) is the solution


    The only way I've found in mdadm to make 2 drives perform like a proper RAID 1 (eg. the read speed should be 2x that of a single drive) is to use the --layout=f2 (far 2). mdadm raid10 performance issues. Be very aware that mdadm seems to default to layout=n2 (which means near). In this scenario it means it is like mdadm RAID 1 performance (you get maximum read speeds of a single drive). dd if=/dev/md126 of=/dev/null bs=1M cou........
  • Centos and obfsproxy install errors


    pip install obfsproxy /usr/lib/python2.6/site-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:90: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning. InsecurePlatformWarning You are using pip version 7.1.0, however version 8.1.1 i........
  • Avocent 8020 KVM Java Icedtea Viewer


    It seems every other updated version of Java or Icedtea breaks things and I will save the frustration of Java for another post. *If you get the icedteaweb window but nothing loads or prompts it is probably your security settings that won't even prompt to run it. See this article to solve that problem. To fix this error you need to edit the java.security file m........
  • Centos 6 how to guide convert LVM non-RAID into mdadm 1/10 RAID array live without reinstalling


    Here is the scenario you or a client have a remote machine that was installed as a standard/default minimal Centos 6.x machine on a single disk with LVM for whatever reason. Often many people do not know how to install it to a RAID array so it is common to have this problem and why reinstall if you don't need to? In some cases on a remote system you can't easily reinstall without physical or KVM access. So in this case you add a second physical or disk or already ha........
  • 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........
  • Installing zoneminder on Ubuntu/Debian Linux Howto


    sudo apt-get install zoneminder [sudo] password for one: Reading package lists... Done Building dependency tree Reading state information... Done The following packages were automatically installed and are no longer required: libuser-perl python-evince kdebase-apps kwrite unixodbc libgnomeprint2.2-data python-soappy vgabios python-metacity hddtemp python-mediaprof........
  • 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........
  • VPN Account Buyers Guide and General Info


    What does VPN stand for? VPN stands for Virtual Private Network and is a secure way of connecting networks and devices. In the context we're talking about it will usually be a client-server solution and not connecting whole networks or businesses. The assumption is that most people reading this are trying to secure their internet connection, privacy and hide or change their IPaddress. Why use a VPN? There are many........
  • KVM: unknown exit, hardware reason 0x80000021 kvm_run returned -22 solution


    If the below is happening on KVM (a very weird and scary looking error) it's probably because of Windows. This has happened countless times to me where the bootsector on Windows 7/2008 becomes corrupted easily (even by a crash or shutdown). KVM: unknown exit, hardware reason 0x80000021 kvm_run returned -22 rax 0000000000000010 rbx 0000000000000080 rcx 0000000000000000 rdx 0000000000000080 rsi 000000000025db2a rdi 000000000007db2a rsp 0000000000000200 rbp........
  • CPanel Link to all of the command line options


    CPanel says you can access 98% of the functions through CLI which experienced Unix/Linux admins prefer for simplicity and for scripting.  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. So for people like me here's the list: http://cpanel.net/system-administrators/command-line-scrip........
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    Say if you have a form/button like this: ........
  • CPanel Apache httpd won't start solution: Starting httpd: Syntax error on line 2 of /etc/httpd/conf/httpd.conf: Invalid command 'Alias', perhaps misspelled or defined by a module not included in the server configuration


    root@hkhosting [/]# service httpd start Starting httpd: Syntax error on line 2 of /etc/httpd/conf/httpd.conf: Invalid command 'Alias', perhaps misspelled or defined by a module not included in the server configuration ........
  • Howto Execute PHP from within an HTML or other file with an htaccess file on Apache


    Add this to a new ".htaccess" file inside the directory where the .html resides: AddType application/x-httpd-php .php .html........
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    yum -y install fail2ban vi /etc/fail2ban/jail.conf [asterisk-tcp] enabled = true filter = asterisk action = iptables-multiport[name=asterisk-tcp, port="5060,5061", protocol=tcp] sendmail-whois[name=Asterisk, dest=you@example.com, sender=fail2ban@example.com] logpath = /var/log/asterisk/messages maxret........
  • KVM on Centos 6.3 cannot boot FreeBSD 9.2 AMD64


    On the same OS with the same kernels basically I cannot boot FreeBSD installer, I believe the issue is the host CPU. One host runs an Intel and works, while an Opteron 2373 does not work despite suggestions from this thread: http://149.20.54.209/showthread.php?t=36761 I've tried cpu options like "kvm64" "Opteron_G3" and none........
  • Unixbench Testing


    The first is a dual CPU AMD Opteron 2373EE (4 cores x 2) and I think it did bad because it has some old 250GB SATAs which can only do about 65MB/s max sequential reads. I think it should have blown away the second (AMD X4 640 Quad Core). [root@fs12home unixbench-4.1.0-wht-2]# ./Run make all make[1]: Entering directory `/root/unixbench-4.1.0-wht-2' Checking distribution of files ./pgms exists ./src exists........
  • Dell FS12-NV7 2U Server Information and Guide


    I've got one of these for testing projects from work at home and got more than I bargained for with the time I've spent on it due to the storage handing/Perc 6/i cards. My particular model came with the following: 2U Rack Mount Server with Rails 2xOpteron 2373 EE (Quad Core, there is a 6-core version that can be found at times) 16GB RAM 2 x 250GB Seagate SATA 2 x Dell Perc 6/i (horrible and a nightmare to work........
  • 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........
  • yum update error


    yum update error Traceback (most recent call last): File "/usr/bin/yum", line 29, in ? yummain.user_main(sys.argv[1:], exit_code=True) File "/usr/share/yum-cli/yummain.py", line 229, in user_main errcode = main(args) File "/usr/share/yum-cli/yummain.py", line 145, in main (result, resultmsgs) = base.buildTransaction() &nbs........
  • package kernel-xen-2.6.18-274.7.1.el5.x86_64 is intended for a x86_64 architecture solution


    package kernel-xen-2.6.18-274.7.1.el5.x86_64 is intended for a x86_64 architecture Linux etc 2.6.18-274.7.1.el5xen #1 SMP Thu Oct 20 17:06:34 EDT 2011 x86_64 x86_64 x86_64 GNU/Linux As you can see above architecture and kernel is 64-bit but I had to force it to install using "--ignorearch" Solution #rpm --ignorearch -ivh kernel-xen-2.6.18-274.7.1.el5.x86_64.rpm Preparing...&nb........
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    table.custom { border-collapse: collapse; border-style: solid; border-width: 1px; border-color: black; font-size: 11px; } table.custom td { border-collapse: collapse; border-style: solid; border-color: black; &........
  • WD 20EARX Dead Again


    Another new drive bad from the start: Jun 2 15:14:18 one-desktop kernel: [15895.386779] ata2.00: exception Emask 0x50 SAct 0x1 SErr 0x280900 action 0x6 frozen Jun 2 15:14:18 one-desktop kernel: [15895.386782] ata2.00: irq_stat 0x08000000, interface fatal error Jun 2 15:14:18 one-desktop kernel: [15895.386784] ata2: SError: { UnrecovData HostInt 10B8B BadCRC } Jun 2 15:14:18 one-desktop kernel: [15895.386788] ata2.00: cmd 60/0........
  • Linux/ffmpeg How to remove audio from a video solution


    ffmpeg -vcodec copy -i 20130526_195809.mp4 -an 20130526_195809-noaudio.mp4 Withotu the -vcodec copy I got this error (so make sure you use the vcodec copy switch): Error while opening encoder for output stream #0.0 - maybe incorrect parameters such as bit_rate, rate, width or height ........
  • WD 20EARX 2TB Bad within days


    This is just trying to read 5GB off the drive with dd and the drive initially tested ok but shortly after I wondered why I was seeing 2MB/s read speeds. Notice the "current_pending_sector", anytime I've seen it at anything above 0 even with no other bad fields/attributes, it means the drive is bad. ata1.00: exception Emask 0x0 SAct 0x3 SErr 0x0 action 0x0 ata1.00: irq_stat 0x40000008 ata1.00: failed command: READ FPDMA QUEUED ata1.00: cmd 60/00:00:........
  • SMARTCTL Enable SMART on Device Solution for Error "Device does not support SMART Error Counter logging not supported"


    smartctl -a /dev/sda smartctl version 5.36 [i686-pc-linux-gnu] Copyright (C) 2002-6 Bruce Allen Home page is http://smartmontools.sourceforge.net/ Device: ATA WDC WD1600YS-01S Version: 20.0 Serial number: WD-WCAP03024940 Device type: disk Local Time is: Mon Apr 29 21:40:07 2013 PDT Device does not support SMART Error Counter logging not supported........
  • Toshiba Hard Drive Warranty RMA Serial Number Info


    Here's the link to the warranty checker and from there you can also create an RMA: https://myapps.taec.toshiba.com/myapps/admin/jsp/webrma/addRequest1NoLogin.jsp Note that the serial# shown in SMART is not complete as is the case for many other brand sof HDDs. For example a 2TB Toshiba shows the following Serial Number in SMART: Device Model:........
  • Bad Hard Drive Slows Down Computer


    Here's a proven example of what a bad hard drive can do, it was technically functioning OKin a RAID array but the system became extremely low and the load become high and IOWAIT was even higher and I always thought it was a bad application. The truth is that this failing 1TBHitachi has slowly gotten worse and caused huge slowdowns, (eg. 100% load on Thunderbird waiting for e-mails to load etc..). After swapping it out, tabs change instantly, emails are not lagged, and........
  • Hitachi Serial Numbers for Hard Drives without seeing the physical drive


    Here's what SMART tells me the serial number is: === START OF INFORMATION SECTION === Device Model: Hitachi HDS721010CLA332 Serial Number: JP2940HQ3ZY7KH Firmware Version: JP4OA3EA User Capacity: 1,000,204,886,016 bytes Device is: Not in smartctl database [for details use: -P showall] ATA Version is: 8 ATA Standard is:&nb........
  • How To Test If Your Hard Drive Is Good/Signs of dying hard drive


    I like dd, although it only reads it, usually a read test of the entire disk will uncover if your hard drive is bad in some parts. This is a good thing to do at least once a month, a lot of times bizarre program behavior, laginess and crashing/unnmounting problems etc.. are due to a failing disc and SMART won't know it or indicate a problem: We must also remember there's never a guarantee, I've found that ever since we moved to larger and more platters per drive with 1TB drives........
  • smart is not smart, it thinks a dead drive is still good


    I had a dying drive that smart thought until it totally disappeared was a good drive, and actually all parameters did look fine but this system was causing my system to lockup and other bad behavior: === START OF INFORMATION SECTION === Device Model: WDC WD20EARS-00MVWB0 Serial Number: WD-WMAZ20139 Firmware Version: 50.0AB50 User Capacity: 2,000,398,934,016 bytes Device........
  • Hitachi 2TB HDS5C3020ALA632 drive DOA


    I had one of these shipped and it was not recognized when plugged in, here's what a dead drive looks like (I assume it's teh circuit board which is dead): ata1: link is slow to respond, please be patient (ready=0) ata1: softreset failed (device not ready) ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300) ata1: link online but device misclassified, retrying ata1: link is slow to respond, please be patient (ready=0) ata1: softreset f........
  • Apache High CPU Usage Enable Mod_Status Guide Solution - Find Cause of High CPU Usage Script/Domain


    mod_status is a great way to track down the source of high CPU usage and to find what vhost/script is the cause of it. It gives you a live view of bandwith usage, CPU usage, and memory usage broken down by domain/vhost and script/URI. Enable mod_status vi /etc/httpd/conf/httpd.conf ExtendedStatus On SetHandler server-status Order Deny,Allow Deny from all All........
  • Are my WDEARS20 Drives dying already?


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  • Linux High IOWAIT updatedb can't be killed and crash with mdadm


    high IO wait 424 root 39 19 1900 848 552 D 0.0 0.0 0:00.91 updatedb root 424 0.0 0.0 1900 848 ? DN Mar11 0:00 /usr/bin/updatedb -f sysfs?rootfs?bdev?proc?cpuset?binfmt_misc?debugfs?sockfs?usbfs?pipefs?anon_inodefs?futexfs?tmpfs?inotifyfs?eventp........
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  • Linux - mptbase/MPT Fusion LSI Logic Error mptbase: ioc0: ERROR - didn't initialize properly! (-1)


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  • CPU #1 not responding - cannot use it.


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  • updatedb/mdadm caused a kernel panic?


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    This really made me nervous but notice the mdstat says "check". This is because in Ubuntu there is a scheduled mdadm cronscript that runs everyday on Sunday at 00:57 that checks your entire array. This is a good way because it prevents gradual but unnoticed data corruption which Inever thought of. As long as the check completes properly you have peace of mind knowing that your data integretiy is assured and that your hard drives are functioning properly (I'........
  • mdadm won't boot due to fsck error


    Nov 29 20:17:58 ubuntu kernel: [ 1157.180789] md: md1 stopped. Nov 29 20:17:58 ubuntu kernel: [ 1157.180829] md0: unknown partition table filesystem not responding/reading properly with du or rsync (this needed an fsck). [ 2571.489217] EXT3-fs error (device md2): ext3_lookup: deleted inode referenced: 35923106 [ 2571.942299] EXT3-fs error (device md2): ext3_lookup: deleted inode referenced: 35923110 [ 2571.9568........
  • Nautilus/GNOME File Manager handy list of extensions


    nautilus-gksu - privilege granting extension for nautilus using gksu nautilus-sendto - integrates Evolution and Pidgin into the Nautilus file manager nautilus-share - Nautilus extension to share folder using Samba nautilus-actions - nautilus extension to configure programs to launch nautilus-bzr - Bazaar (bzr) integration for nautilus nautilus-cd-burner - CD Burning front-end for Nautilus nautilus-clamscan - Antivirus scanning for Nautilus n........
  • GNOME/Ubuntu how to navigate without a keyboard


    The most basic is the start menu, which is accessed with Alt+F1........
  • Realtek r8169 1gbit/1000mbit NIC/Ethernet Goes Down/Halts on Large File Transfer/Heavy Network Usage


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  • Unixbench Score on Core i5 750 with OpenVZ Kernel vs Xen/Openvz


    This was unbelievable how much the Xen kernel slows things down, keep in mind both tests were done on the hostnode, one was with the Openvz-Xen hybrid kernel and the other was just OpenVZ. You can see the performance difference is nearly 300% better when not using the Xen kernel. OpenVZ-Xen Kernel Test Results (I was wondering what was wrong/so slow with my Core i5!) # # # # # #&n........
  • SSH Automatic/Passwordless Logon - Setup Public Key Encryption In Single Command


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  • Seagate 7200.11 firmware defect in 500GB, 1000GB (1TB) and 1500GB (1.5TB) Hard Drives


    Seagate Inventory/Firmware Check I heard about this issue a long time ago but never looked into it. I figured I wasn't affected since my 500GB drives were running for so long. I've been using Seagate's since 2002 and to this day all of the drives I have are alive from Seagate. *Update the bad news is that I realize one of my 500GB's is about to die, it's not even a year old, but is also not affected by the recall according to Seagate! Seagate Inventory/Firm........
  • Monitor MB/s Disk IO Usage/Bandwidth - Use iostat from the sysstat Package


    The binary "iostat" comes from the package "sysstat" and is available on all Linux/Unix like platforms. Use the "-m" option to give you what you probably want, which is to see in MB/s how much bandwidth each disk is doing. iostat -m Linux 2.6.24.2 ((none)) 04/16/10 avg-cpu: %user %nice %system %iowait %steal %idle ........
  • Picking an FTPD (vsftpd) Server in Linux Centos/Debian


    I decided on using yum to help me decide even though I normaly use proftpd I decided to see what else I could find. yum search ftp Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * rpmforge: ftp-stud.fht-esslingen.de * base: mirrors.netdna.com * updates: updates.interworx.info * addons: yum.singlehop.com * extras: mirrors.netdna.com rpmforge........
  • OpenVZ backup container to a single file while it's running using "vzdump"


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  • Windows XP How To Edit/Find Recent Documents and "File -> New" Templates to create New Word Document, Text/Notepad, Excel etc...


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  • PHP cannot access /usr/bin/openssl


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  • JavaScript get valued of selected <select> drop down l


    JavaScript get valued of selected drop down l [code:1:4be190f44a]Package = OrderForm.package.options[OrderForm.package.selectedIndex].value;[/code:1:4be190f44a] OrderForm = Name of HTML form the SELECT is inside package = Name of SELECT element eg. JavaScript says form name is not defined even though it is I've integrated this into my design and I got an error saying the Form Name i........
  • Javascript window.onLoad


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  • Vonage & Linksys Offer Trade-In Program


    Vonage & Linksys Offer Trade-In ProgramVonage & Linksys Offer Trade-In Program Monday, June 13 @ 09:22:36 PDT Vonage is offering customers a way to get a free 802.11g router when they turn in their old one. advertising For a limited time, customers can trade-in their used router any brand, any model for a Linksys Wireless-G Router with 2 Phone Jacks for broadband telephony (WRTP54G) for free (after rebates), when they si........
  • Asterisk Queue Context Explained


    Asterisk Queue Context ExplainedThis was never explained in voip-info or any other site I read. It is understood you can escape to a context from a queue and how to specify it. [b:882f1e0aee] What is NOT mentioned is that the context= you specify within the queues.conf refers to a [i:882f1e0aee]context that exists in extensions.conf[/i:882f1e0aee][/b:882f1e0aee] This will save you headaches if you need to escape from the queue :)........
  • Telus Begins Enforcing Bandwidth Caps


    Telus Begins Enforcing Bandwidth CapsIt appears Telus has begun to send e-mails out and is planning on enforcing bandwidth caps of only 10gigs/month for their 1.5mbit plan and 20gigs/month for 2.5mbit The state of Canadian ISPs is horrible :( In the east coast, Bell Sympatico will allow you to have unlimited bandwidth and even Aliant will and they have 3mbit for a much more affordable price than our 2.5mbit on Telus. Telus needs to get wit........
  • Process/Parse PHP from HTML files using .htaccess and allowoverride


    RemoveHandler .html .htmAddType application/x-httpd-php .php .htm .html Just add the above into the .htaccess file for your website. Also remember that you need to be allowed to override the Apache and this should go into the vhost for your site as shown below: # you need the AllowOverride otherwise .htaccess directives will be ignoredOptions FollowSymLinksAllowO........
  • Clustered/Distributed Network Filesystems, Which Ones live up to the hype?


    I've tried to find a good sensible solution to cluster with and each technology has it's pros and cons and there is no perfect solution and I've found a lot of "exaggerations" in the applications, benefits and performance of these different filesystems. DRBD I first started off with DRBD and Ihave to say it does live up to the hype, is quite reliable (although it can be annoying to match up the kernel module and user applications since they must match and whe........
  • Unixbench Score with Glusterfs/Openvz & Quad Core Xeon


    This is very disappointing since GlusterFS markets itself as a solution to deploy VPS servers on. On the HNitself I get a Unixbench of about 360. I'm also using an SSH tunnel to secure the communications, but even before that, things seemed very slow. # # # # # # # #####&n........
  • Timezone Change/Updated for Linux/Unix Debian/Fedora/Ubuntu/Centos Change Update Time zone


    This way should work on all Linux machines, at least RHEL/Debian (Ubuntu) based distros but most likely all and also should work on many Unix style machines I believe. Many OS's have tools to update the timezone, but most of them (even if command line) require several bloated packages and even Xorg/KDE based packages etc.. Your time zone info file is actually in /etc/localtime if you open this file in vi/vim/pico you'll see it's gibberish (binary code or another encodin........
  • Writing/Burning a data CD-R/DVD-R or DVD+RW in Unix/Linux


    There's a lot of outdated information and confusion for system administrator's out there. One annoying task for many an Administrator has been backing up data in Linux. You don't need any GUI tools such as K3B or GnomeBaker. Both are excellent tools but for veteran command line users working remotely, using the keyboard is a great and possibly automated way to save yourself pain and hassle. At a later date we'll cover how scripting can automatically backup certain........
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