/ - rtt - IT Resource

  • grep regular expression match number range between specific numbers


    grep -E servers1[2-6] somefile.txt The 1 before the [ bracket means that the number must start with one and can be between 1 and [2-6] or in plain English between 12-16.  ........
  • bash how to print out lines of text within a range from the first occurrence


    #get line number of occurrence in text file and then print out x lines from that point #get the line number of the first occurrence of our search text linenumber=`grep -n "someuniqueitem" inventory.txt|head -n1|cut -d ":" -f 1` #linestop represents how many lines after the occurring line we want to print out in this case "20" linestop=$((linenumber+20)) # sed prints out the line range we want f........
  • bash script how to to check LAN computers for open ports


    In this case it just searches for port 80 it is fairly handy if you have some sort of appliance or something else you aren't sure of the IP of Of course change the port 80 port to whatever port(s) you want. for ip in `arp -n|arp -n|tail -n +2|head -n -1 |grep -v incomplete|awk '{print $1}'`; do  echo "checking $ip:80"  nc -w 1 -z $ip 80  if [ "$?" == 0 ]; then   echo "**Port 8........
  • systemd management using systemctl and journalctl to check systemd logs


    systemd is like the service manager for your Centos and other modern Linux distributions (including Debian/Mint/Ubuntu) allows you to enable services, stop them, restart them, check their status and even reboot your system. The key commands or arguments you will use with systemctl are the following: Unit Commands:   list-units [PATTERN...]         List loaded units &nbs........
  • AMD Set Fan Speed and Other Powerplay Memory/CPU Timings with a Linux script


    You can do other things but this particular script is just to set all AMD cards to 80% fan speed (remember this script needs to applied everytime you reboot). You could set it is a cron or just throw it into /etc/rc.local basepath=/sys/class/drm for hwmon in `ls -1 /sys/class/drm|grep card[0-99]$`; do echo card=$hwmon; hwmonname=`ls $basepath/$hwmon/device/hwmon|grep hwmon[0-99]` hwmonpath=$basepath/$hwmon/device/hwmon/$hwmonname echo "ec........
  • hwloc-nox set CPU affinity in Linux


    sudo apt-get install  hwloc-nox Reading package lists... Done Building dependency tree       Reading state information... Done The following NEW packages will be installed:   hwloc-nox 0 upgraded, 1 newly installed, 0 to remove and 530 not upgraded. Need to get 151 kB of archives. After this operation, 453 kB of additional disk space will be used. Get:1 http://archive.ubuntu.com/ubunt........
  • gvfs mount in /run/user cannot be accessed or displayed wrong permissions


    The folder contents could not be displayed Backend currently unmounting drwx------ 10 userhere group  260 Aug 23 19:40 .. ??????????  ? ?   ?      ?            ? sftp:host=192.168.8.80,user=adhoc ls: cannot access 'sftp:host=192.168.8.80,user=adoc': Input/output error $ ps aux|grep fuse one       253........
  • 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 PHP 7 installed so if you reference PHP 5 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........
  • VMWare ESXi 6.7 SSH/PowerShell CLI Commands


    [root@localhost:~] BootModuleConfig.sh          echo                         host-ind                     nfcd                   ........
  • VMWare Vsphere VCSA Graphical Install Creates json


    yes it does create its own json ============================================ cat /tmp/vcsaUiInstaller/ovftool-20180809-175238948-20180809-175603497.log |grep -i json 2018-08-09T17:56:04.238-07:00 verbose OVFTool[30966] [Originator@6876 sub=Default] Manifest file entry: SHA1(VMware-vCenter-Server-Appliance-6.7.0.12000-8832884_OVF10-file1.json) = 1deb658c724767697587d5909c4051c01813e6a1 -->     <ovf:File ovf:href="VMware-vCenter-Server-........
  • [warn] VirtualHost 10.2.5.101:443 overlaps with VirtualHost 10.2.5.101:443, the first has precedence, perhaps you need a NameVirtualHost directive


    [root@thetor2017 conf]# service httpd restart Stopping httpd:                                            [  OK  ] Starting httpd: WARNING: MaxClients of 3000 exceeds ServerLimit value of 300 servers,  lowering MaxClients to 300.  To increase........
  • named [FAILED] - zone 1.168.192.in-addr.arpa/IN: not loaded due to errors. - bind error solution


    Centos when copying old files and restarting it seems load everything fine and then says [FAILED] with no log or other message. service restart named named   [FAILED] Check more thoroughly you may have missed the error if you have lots of zones!  service named restart|grep error zone 1.168.192.in-addr.arpa/IN: not loaded due to errors. zone 2.168.192.in-addr.arpa/IN: no........
  • MySQL Cannot Update/Write to any database table solution


    This happened on Centos for no apparent reason with no obvious issue in the logs.  Data could be read fine but not written (possibly due to some corruption or out of memory issue in the OpenVZ container is the best guess).   All mysql update and insert queries failed freezing without any error log on any database and table. Tried to restart: service mysqld restart Timeout error occurred trying to stop MySQL........
  • pcimodules and lspci not working alternative solution


    pcimodules no longer works it produces nothing probably because the format of /sys/bus/pci is different. lspci -k doesn't work on older lspci versions. pciutils can be compiled but it won't work if you have an old system and compile on a newer glibc. iteriate through /sys/bus/pci/devices/*/modalias cat /sys/bus/pci/devices/*/modalias pci:v00008086d00001237sv00000000sd00000000bc06sc00i00 pci:v00008086d00007000sv0000000........
  • mdadm how to mount inactive array


    myguy@devbox:~$ sudo mdadm -As myguy@devbox:~$ cat /proc/mdstat |grep sdf md125 : inactive sdf3[2](S) sudo mdadm --manage /dev/md125 --run mdadm: started /dev/md125  ........
  • How to find and mount mdadm arrays automatically


    A great way if you have a bunch of drives and mdadm connected and are looking for backups/archives and don't know what is where!    for md in `cat /proc/mdstat|grep md[0-99]|awk '{print $1}'`; do mkdir /mnt/$md; mount /dev/$md /mnt/$md; done........
  • rsync specify alternate port non-standard port than 22


    It is not obvious but the rsync --help  rsync --help|grep port      --port=PORT             specify double-colon alternate port number --port does not do anything at all actually for some strange reason it still uses 22 You have to specify a manual ssh command to make it work: -e 'ssh -........
  • Wine uninstalled broken on Linux Mint


    Solution: Aptitude is very smart and fixed the issues it was because of nvidia cuda and opencl and nothing else suggested or hinted this using apt sudo aptitude install wine The following NEW packages will be installed:   ocl-icd-libopencl1{ab} ocl-icd-libopencl1:i386{ab} wine wine1.6   wine1.6-amd64{a} wine1.6-i386:i386{a} The following packages will be REMOVED:........
  • Linux Mint USB Kernel Tainted and Locked Port/Dev File


    Essentially a program I was running for mining did not terminate properly with Ctrl+C it is listed as defunct and cannot be killed, kernel is tainted and normal tricks to disable the port are impossible the dev and sys entries for the device cannot be browsed or interacted with in any form without a lockup of the request.  The only solution is to reboot due to the kernel taint as far as I can find so far.   [1130246.811056] INFO: task minerd:21861 blocked for more th........
  • 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:   <nuser> Last mounted on:          /mnt/md50 Filesystem UUID:          976a8655-2619-4587-878c-dab07f7b7652 Filesystem magic number:  0xEF53 Filesystem revision #:    1 (dynamic) Fi........
  • Why won't my Linux Mint boot after I manually installed a new kernel?


    Why won't my Linux Mint boot after I manually installed a new kernel? eg. apt-get install linux-image-newerone Do this   dpkg -l|grep linux-image|grep extra ii  linux-image-extra-3.16.0-38-generic                         3.16.0-38.52~14.04.1     &nb........
  • Linux how to whois query other gTLDs such as .club solution


    whois in Linux is incredibly out of date and does not seem to recognize most new TLDs domains, but there is a quick and easy tip/hack/tweak for this. An example of new TLD's site as .review .site .club whois somesite.club No whois server is known for this kind of object.   bash to the rescue Now I did try to apply this in .bashrc but DO NOT!  I think the * wil........
  • Linux how to reformat html file code solution


    The solution is simply "tidy"/Tidy-HTML.  It will take your poorly formatted HTML code (and I mean files that span just a few lines that are unreadable) and fix it up. Note the command below does everything in place.  *Make sure you take a backup of all .html files* It also seems to break html5 code/templates so beware. tidy -im yourfile.html An automated way in bash:........
  • grep only certain file types howto


    This can save a lot of time, otherwise grep will go through an entire directory recursively searching every type of file but what if you are sure you only need to search txt or php files? grep -r -i --include=*.php "what you are searching for" /the/path/to/search........
  • Apache Log Error Message when starting


    Usage: geoiplookup [-h] [-?] [-d custom_dir] [-f custom_file] [-v] [-i] [-l] <ipaddress|hostname> Usage: geoiplookup [-h] [-?] [-d custom_dir] [-f custom_file] [-v] [-i] [-l] <ipaddress|hostname> grep: Address: No such file or directory grep: not: No such file or directory grep: found: No such file or directory sh: -c: line 1: syntax error near unexpected token `|' sh: -c: line 1: `|cut -d ',' -f 2'  ........
  • Linux Mint/Ubuntu/Debian Window Controls Missing Solution


    If Linux Mint 17 or other has no window buttons/controls you can do the following from terminal: marco --replace& Sometimes it can be fixed if you go to your themes/appearance and choose a new one but in the case like mine where Compiz is installed but not running/working then that fix will not work and will require the marco command above. What if you can't type in a terminal Window? If you close........
  • bash script Get Model and Serial Number of All Hard Disks in Server on Linux


    for disk in `fdisk -l|grep "Disk /dev"|awk '{print $2}'|sed s/://g`; do echo "$disk" && smartctl -d ata -a "$disk" -T permissive|grep -iE 'Device Model:|Serial Number:' echo "---------------" done *Make sure you have smartctl from smartmon tools installed   Sample output: /dev/sdc Device Model:   ........
  • Centos yum mirror problem error "[Errno 14] PYCURL ERROR 22 - "The requested URL returned error: 404 Not Found""


    [Errno 14] PYCURL ERROR 22 - "The requested URL returned error: 404 Not Found" The above happened when for some reason all the mirrors in my cache didn't have the files (some mirrors only keep the latest version of Centos). I tried to block them all but that didn't help because it seemed the mirrors were all hardcoded no matter what I tried. Here is how to fix it and reset your mirror list in Centos cd /var/cac........
  • cPanel how to force reinstall rpms and fix packages and other problems caused by updates or duplicate rpms


    <p>If a service is not working and resetting it to defaults is not working and you get bizarre error messages it is probably a broken update and possibly duplicate package.</p> <p>Take in this case &quot;exim&quot; not working even after resetting to defaults.</p> <p><strong>Check for duplicates:</strong><code><br /> </code></p> <p><code>rpm -aq|grep exim<br /> </code></p> <p><c........
  • Linux bash how to list files of a certain date with the statu command for scripting


    The command below will show only files created for the month of 2014-12 but you can of course change the year, month or even specific day or time to suit your needs.   The awk command simply just makes it output the list of files created on the date you are looking for. stat -c "%z %n" *|grep ^"2014-12"|awk '{print $4}'........
  • Vbox/Virtualbox devices grayed out for non-root user solution


    <p>It is a permissions issue that is hard to fix.</p> <p><strong>All but one USB device is greyed out.</strong></p> <p>I am already a member of &quot;vboxusers&quot;</p> <ul> <li>I have already enabled and disabled USB support for the guest.</li> <li>I have already reinstalled the latest VBOx guest editions</li> <li>If running as root it all works fine</li> <li>Changing........
  • bash shellshock how to manually patch when there is no update for Centos/Debian/Ubuntu/Fedora


    wget http://ftp.gnu.org/gnu/bash/bash-4.3.tar.gz tar xzvf bash-4.3.tar.gz cd bash-4.3/ wget --no-directories --level 1 --recursive http://ftp.gnu.org/gnu/bash/bash-4.3-patches/ for patch in `ls bash43-*|grep -v .sig$`; do echo applying "$patch" patch -p0 < $patch done ./configure;make;make install #it will install to /usr/bin/bash but if your bash is somewhere else you need to overwrite the old one.........
  • OpenVZ mismatched kernel and dev when compiling.


    ./configure ./configure: line 91: cd: /lib/modules/2.6.32-042stab084.25/build: No such file or directory Error: kernel version not found. Please make sure your kernel is configured. dr-xr-xr-x.  4 root root   4096 Feb 21 06:13 .. lrwxrwxrwx   1 root root     45 Feb 21 06:13 build -> ../../../usr/src/kernels/2.6.32-042stab084.25 drwxr-xr-x   2 root root   4096 Feb 12 20........
  • How to read a conf file without the comments


     cat /etc/some.conf|grep -Ev '^#|^;|^$' This assumes that comments start with # or ; (adjust as necessary).  Also note that the ^$ omits blank lines.........
  • Linux Bash grep howto find line number that contains the result


    cat Xorginfo.txt|grep -nr "xserver-xorg" Result: 9:    sudo apt-get remove --purge xserver-xorg 13:    sudo apt-get install xserver-xorg 17:    sudo dpkg-reconfigure xserver-xorg........
  • Linux find what processes are swapping


    Here is a handy script that will check all processes and report what is swapping #!/bin/bash for pid in `ps x|awk '{print $1}'`; do result=`cat /proc/$pid/status|grep VmSwap|awk '{print $2}'|grep -v ^"0"` if [ ! -z "$result" ]; then  programresult=`ps x|grep $pid|grep -v grep`  if [ $? == 0 ]; then      program=`echo $programresult|awk '{print $5}'|grep -v ^grep`........
  • CPanel suhosin install failed


    /scripts/phpextensionmgr install PHPSuHosin Updating md5sum list Fetching http://httpupdate.cpanel.net/cpanelsync/easy/targz.yaml (connected:0).......(request attempt 1/12)...Resolving httpupdate.cpanel.net...(resolve attempt 1/65)...     Fetching http://httpupdate.cpanel.net/mirror_addr_list (connected:0).......(request attempt 1/3)......connecting to 74.50.120.123...@74.50.120.123......connected......receiving...100%......request success......Done........
  • Dell Perci 6/i Firmware Upgrade Guide Tutorial


      One thing to remember is that you need MegaCli to do the flashing. You also need the correct file, I tried at least 2 different Perc 6 firmwares from Dell that kept getting rejected as corrupt by MegaCli (they were really the wrong version).  I have an external PCI-E Dell 6 Perc/I but I chose images from the 'Integrated" on motherboard version as it was all I could find.  They are different, and below is my first time finding success.........
  • Dell Perc 6/i cannot downgrade


    I flashed an LSI Logic firmware to it and it broke the BIOS (cannot do Ctrl+R) for booting purposes but allows other functionality to work normally. I tried downgrading to a Dell firmware for Perc 6i but it won't work, not even with MegaCli wget http://downloads.dell.com/FOLDER00416606M/1/SAS-RAID_Firmware_W83M2_LN32_6.3.1-0003_A14.BIN --2013-08-26 12:53:39--  http://downloads.dell.com/FOLDER00416606M/1/SAS-RAID_Firmware_W83M2_LN32_6.3.1-0003_A14.BIN Resolvi........
  • Bash weird variable whitespace missing when echoing printing


    Bash weird variable whitespace missing var=`cat tlds.csv|grep .ca,` # echo "var=:$var:" :ar=:.ca,Canada Why is the v missing in the last line? It should be :var=:.ca,Canada instead of :ar=:.ca,Canada I noticed a problem with the file with doing a "cat -v" on it. Here's the issue, the file contains carat M ^M: .vg,British Virgin Island........
  • mkdir: cannot create directory 'test': Disk quota exceeded - Solution


    mkdir: cannot create directory 'test': Disk quota exceeded You are out of inodes usually: df -i Filesystem            Inodes   IUsed   IFree IUse% Mounted on /dev/simfs            200000  200000       0  100% / none      ........
  • Nearly 100% CPU Usage from processes called dma0chan0 dma0chan1 dma0chan2 dma0chan3


    I never started these processes but they are from a custom based bootable Linux I've made and I've never seen this behavior on other machines or even with the same machine using different kernels.  These processes seemed to spawn on their own and I have no idea why and even worse why the CPU usage is so high? Here's the output from top:   907 extaudit  30  10     0    0    0 R 90.7  0.0 ........
  • Thunderbird How-To Copy/Backup/Restore Accounts and Settings to Another Computer


    The best way is to use rsync, I've set it up so it doesn't copy unnecessary files, or at least ones I'm sure aren't needed. Here is the rsync command I used (adapt to your specific Thunderbird profile location): rsync -hazv user@remotehost.com:/home/user/.thunderbird/sbrer.default/* /home/user/.thunderbird/4nyb0.default/ --exclude=global* --exclude=Cache --exclude=ImapMail --exclude=Mail This is a great way to get your e-mail accounts going on a new c........
  • ntpd[7047]: can't open /var/lib/ntp/drift.TEMP: Permission denied solution


    ntpd[7047]: can't open /var/lib/ntp/drift.TEMP: Permission denied chown ntp.ntp /var/lib/ntp/ The solution is shown above and changes the ownership to ntp.ntp which is what the ntpd daemon/server is running as.  This is based on Centos but the same idea will apply on any other OS.  You can do a "ps aux|grep ntpd" to see what it is running as in the case it's running as a different user. After that this annoying message wil........
  • Virtualbox Guest Hang/Freeze Ghost Zombie VM Machine Problem/Solution


    Virtualbox hang problem A VM just froze and wouldn't close so I had to force it, but the VBox GUI thinks it's running even when I close it. I manually killed the related process by doing ps aux|grep VirtualBox and found the PID 6191 I killed it with "kill -kill 6191" but it remains open and as "defunct" so I can't restart it because the GUI freezes when I click on it because it thinks it is running still........
  • GREP how to ignore blank lines


    grep -v '^$'........
  • 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........
  • sshfs cannot unmount error: device is busy. (In some cases useful info about processes that use the device is found by lsof(8) or fuser(1))


    umount: /home/diret/mount: device is busy.         (In some cases useful info about processes that use          the device is found by lsof(8) or fuser(1)) I tried everything (fusermount -u) to unmount it but the only thing that worked was actually doing this: ps aux|grep sshfs Then I identified the sshfs connection and did: kill -kill pid........
  • VMWare bridged adapter not working: The network bridge on device vmnet0 is not running. The virtual machine will not be able to communicate with the host or with other machines on your network. Failed to connect virtual device Ethernet1.


    VMWare bridged adapter not working: Message from system: The network bridge on device vmnet0 is not running. The virtual machine will not be able to communicate with the host or with other machines on your network. Failed to connect virtual device Ethernet1. I'm not sure how to fix this but one of the issues is that my eth0 became eth1 after moving my hard drives to a new motherboard.  I have run the vmware-config.pl but this did not resolve the issue.........
  • mdadm Centos 5 automatic resync


    This made me nervous but it's clearly a cronjob based on the messages log that happens every Sunday at about 4:22. I actually can't find any evidence of it in cron.d cron.daily but it is there somewhere obviously. What I don't get is why doesn't this cronjob do a datacheck like Ubuntu's cronscript does?  When you unnecessarily rebuild the array you lose your redundancy during that point which makes your data extremely vulnerable. *Update I did a grep of &q........
  • Ubuntu/Debian DRBD 8.0 Setup Guide


    I've only used it on Centos, so I 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........
  • yum in Centos 5/Xen halts and exits suddenly


    yum exits in the middle The problem is this VPS seems to be an OpenVZ template from HyperVM.  The only way to make it work was to disable i386 packages since this was an x64 kernel.  That shouldn't be necessary but it was the only way to make yum stop quitting after the first package or two.  I couldn't find any issue by checking the logs either. echo y|yum install vim-minimal telnet expect jwhois net-tools slocate iptables elinks gawk L........
  • WD EARS/Green 2TB Cannot Disable Power Saving/Head Parking with hdparm


    hdparm -B 255 /dev/sdb /dev/sdb:  setting Advanced Power Management level to disabled  HDIO_DRIVE_CMD failed: Input/output error   The one thing you can do though is to set hdparm spindown time lower (it doesn't seem to work that well).  -S   set standby (spindown) timeout   hdparm -S 251 /dev/sda /dev/sda:  setti........
  • PHP cannot access /usr/bin/openssl


    PHP cannot access /usr/bin/opensslI have verified the username that runs the process is able to access /usr/bin/openssl and it does exist but the PHP script is saying it doesn't exist: [code:1:1fd0f3abbe] if (!file_exists($OPENSSL)) { //echo "ERROR: OPENSSL $OPENSSL not foundn"; }[/code:1:1fd0f3abbe] I don't get itI can clearly see the contents of /usr/bin by using the PHP system fu........
  • Linux How to Search for text within any file using Linux/Unix - Use GREP


    It's actually very simple and "grep" makes it as easy as possible.  I'll outline a few common scenarios and provide some examples. Say you want to search ALL files within the current directory (and inside/deeper) for the text "phpinfo()" grep -R "phpinfo()" * If you want to search only certain files such as only .txt you would do this instead: grep -R "phpinfo()" *.txt As you ca........
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