• mdadm: super0.90 cannot open /dev/sdb1: Device or resource busy mdadm: /dev/sdb1 is not suitable for this array.


    mdadm --create /dev/md0 --level 1 --raid-devices 2 /dev/sdb1 missing --metadata=0.90 mdadm: super0.90 cannot open /dev/sdb1: Device or resource busy mdadm: /dev/sdb1 is not suitable for this array. mdadm: create aborted Sometimes running "partprobe" can fix this. Other times it requires a reboot. One other manual thing that can be done is the following to fix it (if dm is using and blocking it):........
  • Linux 3D Performance benchmarks with glxgears 59-60fps solution


    You need to disable vsync like this when running glxgears: vblank_mode=0 glxgears Notice the higher than 59-60 fps results with vblank_mode=0: ATTENTION: default value of option vblank_mode overridden by environment. 7919 frames in 5.0 seconds = 1583.704 FPS 8187 frames in 5.0 seconds = 1637.266 FPS 7441 frames in 5.0 seconds = 1488.072 FPS 7436 frames in 5.0 seconds = 1487.076 FPS X........
  • How To Install Asterisk 16 17 on Debian Ubuntu Linux


    Downloading and compiling from source to get the latest version of Asterisk is really simple with this guide. apt install gcc make g++ libedit-dev uuid-dev libjansson-dev apt install libxml2-dev sqlite3 libsqlite3-dev wget http://downloads.asterisk.org/pub/telephony/asterisk/asterisk-16-current.tar.gz tar -zxvf asterisk-16-current.tar.gz cd asterisk-16.6.2/ ./configure If you get this error change y........
  • Linux Ubuntu Debian Centos How To Make a Bootable Windows 7, 8, 10, 2016, 2019 Server USB from ISO


    Use fdisk on your USB drive to create a bootable NTFS partition (in my case /dev/sdb): sudo fdisk /dev/sdb Welcome to fdisk (util-linux 2.27.1). Changes will remain in memory only, until you decide to write them. Be careful before using the write command. Command (m for help): n Partition type p primary (0 primary, 0 extended, 4 free)........
  • python import docx error


    sudo pip3 install python-docx [sudo] password for : Downloading/unpacking python-docx Downloading python-docx-0.8.10.tar.gz (5.5MB): 5.5MB downloaded Running setup.py (path:/tmp/pip_build_root/python-docx/setup.py) egg_info for package python-docx no previously-included directories found matching 'docs/.build' warning: no previously-included files matching '.DS_Store' foun........
  • Linux partprobe/partx cannot access last and 4th partition


    On a test machine Iwas never able to access to a newly created 4th partiton. As we can see there are dev devices for everything but the 4th partition. The normal "partprobe" or "kpartx" or kernel being told to rescan the block device didn't help (only a reboot did). fdisk -l /dev/sda Disk /dev/sda: 750.2 GB, 750156374016 bytes 255 heads, 63 sectors/track, 91201 cylinders Units........
  • VMWare 6.7 VCSA VSphere ESXi Management SSO Install Guide on Linux using the CLI


    #mount the VCSA DVD mount /dev/sr0 /mnt/cd #alternatively you could mount the iso directly mount -o loop vcsa.iso /your/mount/path #for this purpose we are using the CLI installer on Linux cd /mnt/cd/vcsa-cli-installer/lin64 #no it's not going to be that easy you can't just run vcsa-deploy like that you need to use a template or configured .json file ./vcsa-deploy Usage: vcsa-deploy [-h] [--version] [--supported-deploymen........
  • mail command line examples of how to send an email using Linux / Unix and the Bash Shell or Scripting


    A simple way that may work for a lot of people who just need basic output for their scripts or daemons to announce an action is this: echo "body or message" | mail -s "realtechtalk.com" user@domain.com If you want to send a text file as the body just do this instead: mail -s "realtechtalk.com" user@domain.com < /tmp/sometxtfile.txt These are some ve........
  • 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. ****........
  • 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........
  • Linux How To Recover Partition Table from Kernel and Restore Centos/Debian etc..


    We've all done this at some point, you work on the wrong shell window and this was my first time making this mistake but I deleted a partition table in fdisk, recreated it and saved it with "wq" and even ran partprobe! If you haven't rebooted yet then you can still recover your partition table, otherwise you're in big trouble. Fortunately since it was a live system and in use the kernel still had to use the old table like below:........
  • Openvz error solutions Container already locked (error) can't lock quota file, some quota operations are performing for id 1200


    rm /vz/lock/1200.lck rm: remove regular file `/vz/lock/1200.lck'? y vzctl start 1200 Container already locked vzctl start 1200 Starting container ... vzquota : (error) can't lock quota file, some quota operations are performing for id 1200 vzquota on failed [7] vzquota off 1200 vzctl start 1200 vzquota on 1200 root@rttbox ~]# vzquota off 1200 vzquota : (........
  • Centos/obfsproxy errors


    I never did get it working, it is too bad as obfsproxy should really be an option and integrated into the OpenVPN client and server or something similar: yum -y install python-pip python-devel No package python-pip available. #install the EPEL repo python-pip install obfsproxy python-pip install obfsproxy -bash: python-pip: command not found pip install obfsproxy &........
  • Avocent Unable to load resource avctVideo.jar


    Avocent Unable to load resource avctVideo.jar Avocent requires port 80 and 443 to be forwarded or you will get a message like above if it's on a NAT network and you are accessing it from the outside (internet).........
  • ResourceManager[31705]: CRIT: Resource STOP failure. Reboot required!


    ResourceManager[31705]: CRIT: Resource STOP failure. Reboot required! This happened on a cluster Iam running with heartbeat for no particular reason that I can figure out. The box ended up rebooting itself for some reason. It was not a big deal in the sense that the other servers in the cluster kept running but it would be nice to find the cause of this.........
  • mdadm: Cannot open /dev/sda1: Device or resource busy


    This was caused by some weird dmraid setup which kind of takes control of drives even if they're blank/unused. 1. Check the table. dmsetup table ddf1_44656c6c202020201000006010281f0b3f5195b77cf86172: 0 3905945600 linear 8:0 0 ddf1_44656c6c202020201000006010281f0b3f5195b77cf86172p3: 0 37124096 linear 253:0 284547072 ddf1_44656c6c202020201000006010281f0b3f5195b77cf86172p2: 0 283496448 linear 253:0 1050624 ddf1_44656c6c2020202010........
  • kvm cannot boot xen guest using lvm


    This booting error is because the Xen PV guest image uses the Xen kernel, this is not compatible with anything but a host running a Xen kernel. I did a kpartx -av virtual.img and then it created some partitions that showed up in fdisk. I mounted it and did a chroot into it and removed the xen kernel and installed a normal kernel but Xen still shows the same kernel in Grub (only the Xen one). This is strange but it seems like this Xen PV guest has some sort of hidden or........
  • How to recover from dead DRBD partition/hard drive in two simple commands


    This assumes that you've at least created the correct partition for your DRBD already. Notice that I am "diskless", that's because either your DRBD partition doesn't exist/has been renamed (eg. sdb becomes sda when sdb dies and you reboot) or because that drive is really actually dead/gone. *If you need to permanently change the partition/device for your resource be sure to edit /etc/drbd.conf on both hosts and reload the config. (replace r0 with........
  • iPhone 3G/3GS/4 Undelete Photos/Videos Datarecovery


    I found this technique listed in many places which shows you how to use a common Linux tool "dd" to dump the raw partition of your iPhone. I give credit to this site for showing me the correct way to dd from the iPhone, I never thought to try it in the other direction:http://log.ijulien.com/post/182804914/iphone-3gs-data-recovery Requirements 1.) Jailbreak your........
  • Ubuntu/Debian DRBD 8.0 Setup Guide


    I've only used it on Centos, soI thought I'd make a quick Debian guide: Install the DRBD Package apt-get install drbd8-utils Reading package lists... Done Building dependency tree Reading state information... Done The following packages were automatically installed and are no longer required: libswfdec-0.8-0 Use 'apt-get autoremove' to remove them. The following........
  • get_printer_attrs: resource name '/printers/printers' no good! - cups error


    This is what the /var/log/cups/error.log says after my Samsung CLP-310N decided to stop printing. This is a new printer that replaced my CLP-300 and it has been working for a day so far. What happened is that I lifted the top part (not realizing there were rollers on it) and it stopped printing. The network activity light was flashing ,hitting the stop button didn't do anything. Even powering the printer on and off did not help. I have restarted CUPS and SMB on the........
  • heartbeat is stopped for some reason


    heartbeat is stopped for some reason Anyway hnode2 was active and the services are running fine but I see heartbeat has been stopped somehow. Here is the last log I see of heartbeat: [quote:23c84415f5] Sep 9 17:15:32 hnode2 heartbeat: [16738]: info: MSG stats: 9/1762471 ms age 0 [pid16738/MST_CONTROL] Sep 9 17:15:32 hnode2 heartbeat: [16738]: info: cl_malloc stats: 716/51784021 152624/74519 [pid16738/MST_CONTROL] Sep 9 17:15:32........
  • Intrusion Detection Resources


    Intrusion Detection ResourcesI think this could be very useful even for home users in learning how to secure their networks or even offices. http://www.sans.org/resources/idfaq/........
  • Clustering Links


    Clustering LinksI thought this might be interesting for people with spare time. [b:6423c19973]Great clustering article from Linux Mag[/b:6423c19973] http://www.linux-mag.com/2003-11/clusters_01.html [b:6423c19973]General Linux cluster information[/b:6423c19973] http://www.gdargaud.net/Hack/ClusterNotes.html#HighA http://www.faqs.org/docs/Linux-HOWTO/Cluster-HOWTO.html#s3 http://www.yolinux.com/TUTORIALS/LinuxClustersAndFileSys........
  • Have an OpenVZ VPS/Linux Virtual Private Server and nothing works right?


    A VPS Server I had just wasn't working right, code that I migrated there just wasn't working. For example, it kept telling me the connection to the database was unsuccessful, halfway through iterating through results it already had. Then I realized it wasn't my code. Ichecked my /proc/user_beancounters and found this: cat /proc/user_beancounters Version: 2.5 uid resource held maxheld barrier limit failcnt........
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