/ - rtt - IT Resource

  • 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........
  • What is /dev/pts and why do we need it in Linux?


    A quick check in /dev/pts shows a lot of entries but what are they for?:  ls /dev/pts 0  10  12  14  16  18  2   21  23  25  27  29  30  32  4  6  8  ptmx 1  11  13  15  17  19  20  22  24  26  28  3   31  33  5  7  9 Basically they are pseudo-termi........
  • Linux What is umask (user mask) for file and directory creation permissions and how to calculate umask and change the defaults


    umask are the default permissions that are applied when a file or directory are created.  To see this in action simply just "touch filename" or "mkdir somedir" and you'll see what default permissions are applied. The first thing I always tell people you should know is to NEVER change the defaults unless you are making them more restrictive.  But they work well and if you change the defaults you could end up creating a file without permission to read........
  • 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........
  • prosody xmpp server "Failed in all attempts to connect to proxy.eu.jabber.org"


    Aug 13 13:46:33 s2sout2d45040    info    Failed in all attempts to connect to proxy.eu.jabber.org Aug 13 13:46:33 s2sout2d45040    info    Sending error replies for 1 queued stanzas because of failed outgoing connection to proxy.eu.jabber.org No clue why it tries to use a proxy not explicitly specified.  This could be because the proxy specified for the domain fails when someone is trying to se........
  • 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-........
  • Debian Mint Ubuntu compiling xmr-stak


    sudo apt-get install libcurl4-openssl-dev git build-essential autotools-dev autoconf libcurl3 sudo apt-get install libcurl4-gnutls-dev git clone https://github.com/wolf9466/cpuminer-multi sudo apt-get install cmake  libpthread-* libmicrohttpd-dev libssl-dev libhwloc-dev git clone https://github.com/fireice-uk/xmr-stak-cpu.git make install cd bin chmod +x xmr-stak-cpu ./xmr-stak -O xmr........
  • Python SyntaxError: Missing parentheses in call to 'print'


    SyntaxError: Missing parentheses in call to 'print'   This is an annoying issue where the syntax between Python 2 and 3 changed which breaks old scripts. print "hello" #change to print("Hello, World!")........
  • Ethereum Client Errors


    INFO [07-19|12:11:51] Imported new block receipts              count=590  elapsed=8.440s     bytes=74117699  number=4870906 hash=6bc60b…934753 ignored=0 INFO [07-19|12:11:57] Imported new state entries               count=499  elapsed=9.963ms    processed=71076 pending=1526  retry=2&nbs........
  • wodim / cdrecord error cannot burn DVD or BDR .iso Errno: 5 (Input/output error), write_g1 scsi sendcmd: no error


     dvd+rw-mediainfo /dev/sr0 INQUIRY:                [ASUS    ][BW-16D1HT       ][3.00] GET [CURRENT] CONFIGURATION:  Mounted Media:         11h, DVD-R Sequential  Media ID:              RITEKF1  &n........
  • 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 a........
  • Duplicate entry '2147483647' for key 'PRIMARY' MySQL Error Solution


    This usually happens when you are using something like an INT and try to insert a larger value than the maximum which is larger than "2147483647" On a practical term I have seen this and been guilty of this error when using scripts like PHP and generating large random numbers:   $hash = mt_rand(5,9999999999999); Obviously that many 9's are more digits than the maximum of an INT resulting in that error.  Change your code accord........
  • SMF Forums / Simple Machines Forums Not Displaying Images Theme or Styles Properly using 127.0.0.1


    This is one thing that has me wondering about SMF.  It is apparently a known issue but in the latest version and new install nothing looked right because it was using http://127.0.0.1 to find everything!  How on earth would it ever do this or think it is normal? Excerpt of crazy html code it produces that causes the issue:     <link rel="stylesheet" type="text/css&qu........
  • 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........
  • 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........
  • ffmpeg how to watermark and concatenate in one command


    If you were in my boat you were frustrated that you had to double encode, eg. one separate encode for watermark and a separate from concat and it's not easy to figure out this with ffmpeg on your own.  However it is a nice way to save time! ffmpeg -i file1.mp4 -i file2.mp4 -i file3.mp4 -i watermark.png -filter_complex "[0:v]setpts=PTS-STARTPTS[v0]; [1:v]setpts=PTS-STARTPTS[v1]; [2:v]setpts=PTS-STARTPTS[v2]; [v0][0:a][v1][1:a][v2][2:a]concat=n=3:v=1:a=1[v][aout]; [v][3:........
  • 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........
  • 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              ........
  • Migrate Centos 7 from Single HDD to mdadm RAID 10 array:


    Done on Centos 7.3 very important as clearly based on older guides it was a lot easier and more simpler!  Hint do not use grub2-install! One huge caveat if you are an oldschool user or sysadmin who has avoided UEFI booting The normal way will not work here if your Centos was using UEFI.  Newer systems use it by default. The easiest way to check is to do an fdisk -l if your sy........
  • cudaminer freezes Linux Mint taints kernel


    When running cudaminer once it tries to initialize the card the entire screen freezes.  The computer itself is still running but the Xorg is done for, you cannot even switch to another console window and must reboot (even an mdm or Xorg restart does not help). At first cudaminer will give you these errors: stratrum_recv_line failed ...retry after 15 seconds GPU #0: Geforce 210 with compute ca........
  • 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........
  • 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.  I think 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........
  • 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........
  • Centos 7 Migration Guide from Centos 6


    Centos 7 is no cakewalk, there are many fundamental features and basic utilities that are missing or even completely renamed or different! Another shocking thing is to check your NIC it is set by default to not turn on when booting! And by the way there is no more standard eth0 the NIC convention is now "enp0s3" vi /etc/sysconfig/network-scripts/ifcfg-enp0s3........
  • mdadm frozen and doesn't realize array is dead/missing failed due to unplugged drives


    This was a surprising bug but I unplugged all drives for an array md127.  At first it was just 1 drive and mdadm seemed to notice this.  I unplugged the second drive taking the array offline but mdadm did not realize it was offline and still showed a non-existent disk as being part of it.  This created problems trying to unmount it or even to stop this array with mdadm freezing.  As for how to fix it I can only think of making sure you are not in a mounted path of........
  • mdadm zero-superblock to solve md device created on root device


    It is possible to tell mdadm to create an md device on a raw disk even though it will give you an error, it writes a superblock and this corrupts the partition table which can result in your system not booting. To fix it just zero the super-block on the offending device that you made the mistake in. Eg: /dev/sda mdadm --zero-superblock /dev/sda It is also a way of starting fresh if you wanted to create a new array.........
  • 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........
  • 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 Add Multiple IP Addresses in a range without manually setting each static IP


    This is actually very simple and this example assumes your network device is "eth0" In Centos your network config would be the following: /etc/sysconfig/network-scripts/ifcfg-eth0 Take the same path and just add a "-range0" So to add a range create the following file: /etc/sysconfig/network-scripts/ifcfg-eth0-range0 IPADDR_START=192.168.1.50 IPADD........
  • 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........
  • 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    &........
  • 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........
  • Centos automatic ifcfg-eth0 scripts based on list of IPs from bash


    <p>It's a basic script that reads the file &quot;ips.txt&quot; in the current directory and then creates a corresponding ifcfg file</p> <p>&nbsp;</p> <p>&nbsp;</p> <p><code>#!/bin/bash<br /> GATEWAY=192.168.1.1</code></p> <p><code>NETMASK=255.255.255.0</code></p> <p>device=eth0</p> <p><code><br /> counter=0<br /> for ips in `cat ips.txt`; do<br........
  • /usr/libexec/mysqld: The table 'session' is full solution


    First of all if you're getting this error it is a result of extreme database activity.  If you aren't expecting it or it doesn't make sense to you 99% of the time this is a database driven script being exploited (some common examples I see often are things like phpBB being hit by dozens, hundreds or thousands of bots making constant DB write requests).  The easiest way to identify this is to restart MySQL and then run the third party tool "mtop" and you'll see all........
  • 2CO/2Checkout Howto Enable IPN/Notification Setup & Script Info


    https://www.2checkout.com/documentation/notifications/order-created It shows all the parameters that get passed so you can make a simple script to process it. To enable 2CO Notifications you need to do the following: Login Browse to the top right to an icon that looks like a "circle with horizontal lines inside" - Notifications. Enter the appropriate URL for your IPN/Notification processing script (........
  • 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........
  • drbd won't create device if previous partition is on it Command 'drbdmeta 0 v08 /dev/md160 internal create-md' terminated with exit code 40


    This is what fixed it: [root@box13 ~]# dd if=/dev/zero of=/dev/md160 bs=512 count=500 Basically you need to wipe out more than just the 512 byte partition table so 512 bytes * 500 is more than enough to make DRBD happy and think the partition is now empty. The reason this happens is because it gets confused when there is a previous partition with data on the device you are using.   root@box13 ~]# d........
  • OpenVZ avoid vzctl 4.7 and ploop


    <p>OpenVZ has made vzctl version 4.7 default to using ploop which is a big annoyance.&nbsp; No one wants it otherwise we'd use Xen or KVM.</p> <p>Make sure to manually specify vzctl 4.6.1 or you will have issues with old scripts breaking since it defaults to using ploop (a single image like Xen/KVM).</p> <p><a href="https://openvz.org/Download/vzctl/Archives">Here's a list to old versions of vzctl.</a></p>........
  • 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........
  • 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                                           ........
  • Fatal error: Out of memory (allocated 6291456) (tried to allocate 7680 bytes)


    Fatal error: Out of memory (allocated 6291456) (tried to allocate 7680 bytes) This is usually caused by Wordpress, Drupal or other ridiculously inefficient CMS' out there, as a temporary fix you can increase PHP's memory limit but it's best to find the actual culprit, by disabling add-ons and other scripts etc...........
  • Openvz OOM Centos Issue Memory Config Settings Solution


    Linux box13. 2.6.32-042stab076.5 #1 SMP Mon Mar 18 20:41:34 MSK 2013 x86_64 x86_64 x86_64 GNU/Linux even setting privvmpages to a specific setting DOES not affect "free -m" in containers. This is probably a kernel issue  23:36:29 up 159 days,  7:12,  4 users,  load average: 0.42, 0.44, 0.33 [root@box13 ~]# free -m              total  &n........
  • PHP5 Centos 6 displays part of code from PHP file for some scripts


    PHP5 Centos 6 displays part of code from PHP file for some scripts Solution edit /etc/php.ini change  short_open_tag = Off to: short_open_tag = On Then restart Apache and it should be resolved (assuming the scripts failing used <? and ?>)  ........
  • 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........
  • 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 65 MB/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........
  • screen Cannot open your terminal '/dev/pts/0' - please check. solution


    This happens when su'ing to a user and running screen screen Cannot open your terminal '/dev/pts/0' - please check. Solution (not secure for a shared server) chmod 777 -R /dev/pts  ........
  • Execute Local Bash Scripts remotely by SSH


    for ip in `cat fixlist.txt`; do sudo -u apache ssh root@$ip "`cat iptablesrules.sh`" done In the above example we are going to execute the commands within the local file "iptablesrules.sh" on all the machines in "fixlist.txt".  This is a great way of performing server maintenance in a clustered or cloud environment.........
  • Asterisk DOS attack - failed for '173.242.117.192' - Peer is not supposed to register [May 23 15:46:07] ERROR[32748]: chan_sip.c:13158 register_verify: Peer '153' is trying to register, but not configured as host=dynamic


    This happened to a customer Asterisk server and it somehow found the ID of the registration account to the upstream SIP server and was railing connection attempts (it filled up the console and there were literally thousands per second).  Basically this caused all incoming and outgoing calls to fail. It was a temporary fix but the solution was to block that specific IP, it's hard to stop it 100% because the customer needs the default SIP port.........
  • 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........
  • Linux/Debian shutdown/reboot without going through init force


    -bash-3.1# shutdown -rn now Connection to localhost closed by remote host. Connection to localhost closed. Sometimes I work with embedded systems/custom kernels without any of the fancy init scripts and other common Linux basics that most would expect.  This means that often the "reboot" command (which uses an init script) will never work, not only that but it will hang the server and a manual power cycle or reboo........
  • Directadmin error/** Found 7 pre-existing rpmdb problem(s), 'yum check' output follows: e2fsprogs-devel-1.41.12-3.el6.i686 has missing requires of e2fsprogs-libs = ('0', '1.41.12', '3.el6') e2fsprogs-devel-1.41.12-3.el6.i686 has missing requires of l


    Solution To The Following: yum -y install zlib-devel yum -y install e2fsprogs* *** Cannot find /usr/include/et/com_err.h.  (yum install libcom_err-devel) *** Installation didn't pass, halting install. Once requirements are met, run the following to continue the install:   cd /usr/local/directadmin/scripts   ./install.sh Common pre-install commands:  http://help.directadmin.com/it........
  • How to Encode all VOBs from a DVD/Bluray VIDEO_TS folder into an XVID


    In my case I already copied the VIDEO_TS folder to my hard drive. Here is the command for mencoder: mencoder -dvd-device "myvideobackup/VIDEO_TS" dvd:// -ovc xvid -oac mp3lame -lameopts cbr:br=128 -xvidencopts pass=2:bitrate=-700000 -o myvideobackup.avi Replace "-dvd-device myvideobackup/VIDEO_TS" with the location of your backup files or the /dev device of your DVD drive. The -o myvideobackup.avi is of course the name o........
  • Linux/Centos how to block SSH bruteforce/dictionary attacks automatically with denyhosts


    A lot of people become nervous (and understandably so) when checking their auth or security logs, in Centos /var/log/secure and see dozens, hundreds of even thousands of attempted logins to various services, especially SSH. Of course you could manually block these people/IPs but no one has time to read the logs like that, what if some program or script could do it for you? This is what denyhosts does for you, it checks the logs and based on a certain number of failed SSH attem........
  • bash script remove non-printable special characters/white space


    In bash you test like this for problems that can be caused by non-printable characters since if you don't know how to identify it because it basically breaks your script. echo "url=$url" should print something like this normally if you have properly formatted input/text: url=::http://someaddress.com:: But if you have some weird hidden characters (not visible in a text editor of any sort you'll get something like this ::l=::http://s........
  • failed to IDENTIFY (INIT_DEV_PARAMS failed, err_mask=0x80)


    [   12.460014] ata1: SRST failed (errno=-16) [   17.626677] ata1: link is slow to respond, please be patient (ready=0) [   22.480011] ata1: SRST failed (errno=-16) [   27.646681] ata1: link is slow to respond, please be patient (ready=0) [   38.106817] ata1.01: failed to IDENTIFY (INIT_DEV_PARAMS failed, err_mask=0x80) [   48.266676] ata1: link is slow to respond, please be patient (ready=0)........
  • LOG: MAIN PANIC failed to expand condition "${if eq {$authenticated_id}{}{0}{${if eq {$sender_address}{$local_part@$domain}{0}{${if match{$received_protocol}{N^e?smtps?a$N}{${perl{checkbx_autowhitelist}{$authenticated_id}}}{${if eq{$received_prot


    I experienced this with CPanel's Exim after an auto-update (a Google of this error produces lots of complaints with few clear solutions).  In this case I'll put the solution at the top. Run /scripts/buildeximconf to rebuild the Exim config and it should be fine after that.   mail -vs "from test" user@dest.com < .bash_history LOG: MAIN   cwd=/root 4 args: send-mail -i -v user@dest.com LOG: MAIN   &........
  • 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........
  • OpenVPN don't use bridgestart.sh or bridge at all use iptables


    I used the suggested script to bridge from OpenVPN and it took my client's server off-line!  Don't ever use their "sample" scripts if you don't have another way of accessing the server than SSH. I actually found it easier to use iptables to tell it to route IPs based on a certain subnet to route through eth0: iptables -t nat -A POSTROUTING -s 192.168.200.0/24 -o eth0 -j MASQUERADE Replace "192.168.200.0/24" with your subnet of cour........
  • gocr - free Linux OCR (Optical Character Recognition) conversion tool


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  • convert carat ^M/M Windows based text files to Linux


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  • screen Cannot open your terminal '/dev/pts/2' - please check.


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    This is e-mail notification to warn you that your hostname is setup improperly on your system. This is an annoying message and bug with Directadmin, my hostname is set correctly, why does it complain? To get of this message just run this command: /usr/local/directadmin/scripts/hostname.sh yourhostname.com........
  • encrypt bash scripts to hide source code


    http://www.datsi.fi.upm.es/~frosal/ SHC is a program written by the author above that does just that, it's a great little tool to have. Some have said it isn't exactly encrypting the code but just making it hard to read by obfuscating the code. There was also a good discussion about that here:........
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    drup 6.2 install $cd drupgoodinst3883/ [ drupgoodinst3883]$ ls CHANGELOG.txt  cron.php  index.php          INSTALL.pgsql.txt  INSTALL.txt  MAINTAINERS.txt  modules   robots.txt  sites   update.php   xmlrpc.php COPYRIGHT.txt  includes  INSTALL.mysql.txt  install.php        LICENSE.txt  misc  &........
  • Yahoo Mail (email) DNS Server Out Of Date Problems


    I don't expect this to be solved soon but some of Yahoo's DNS servers are out of whack.  I changed the IPs of some nameservers of some domains and now most Yahoo users can't e-mail to those domains! As you can see below by the "No MX or A records for mychangedomain.com", now Yahoo's DNS/mailserver DNS cache is wrong.  You would think they would at least have cached the old incorrect records, but instead for some reason their DNS cache has no entry and doesn't seem........
  • Linux High IOWAIT updatedb can't be killed and crash with mdadm


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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.


    I think this will be useful to others because I have a server that kept crashing mysteriously during intense disk usage/RAID checks.  It would only crash during the weekly RAID integrity check. Then I noticed during a reboot that not all CPUs were being brought up, as a result this actually creates much higher temperatures with the output I got from sensors, just booting the system produced higher than normal temperatures. You can imagine that a full blown RAID check........
  • Ubuntu 9.04 Crash


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  • Failed to save enabled features : The Suexec command on your system is configured to only run scripts under /var/www, but the Virtualmin base directory is /home. CGI and PHP scripts run as domain owners will not be executed.


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  • yum in Centos 5/Xen halts and exits suddenly


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  • How to chroot properly into your OS/distro


    From a LiveCD or if you're doing something like converting your non-RAID install to mdadm here's how you would chroot properly (you have to mount your proc, sys and dev on the running system/LiveCD to your chroot environment if you want things to work right, especially if you need to run update-initramfs due to a driver change etc..) *replace "path" with your mount/chroot path mount -o bind /proc /mnt/path/proc mount -o bind /dev/ mnt/pa........
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  • Directadmin License Error The ip of this machine (xx.xx.xx.xx) does not match the ip in the license file.
    Check the value of your ethernet_dev=venet0:0 setting in your /usr/local/directadmin/conf/directadmin.conf file and the output of /sbin/ifco


    2010:09:09-22:22:11: The ip of this machine (xx.xx.xx.xx) does not match the ip in the license file.<br> Check the value of your ethernet_dev=venet0:0 setting in your /usr/local/directadmin/conf/directadmin.conf file and the output of /sbin/ifconfig<br> Solution /usr/local/directadmin/scripts/getLicense.sh........
  • Direcatdmin Install AWStats


    cd /usr/local/directadmin/scripts/ scripts]# ./awstats.sh --23:49:28--  http://files.directadmin.com/services/all/awstats/awstats-6.9.tar.gz Resolving files.directadmin.com... 72.35.85.222 Connecting to files.directadmin.com|72.35.85.222|:80... connected. HTTP request sent, awaiting response... 200 OK Length: 1125906 (1.1M) [application/x-gzip] Saving to: `/usr/local/directadmin/scripts/packages/awstats-6.9.tar.gz' 100%[=........
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    Different distributions such as Debian and Centos behave differently when trying to shutdown your system. shutdown -H now on Debian does not do what you'd expect.  The system won't power down, it will halt and do everything but power down. shutdown -PH now will do the job though (actually power the system off).  This is important to test especially if you are not near the system.  If you just use -P it forcefully shuts off which is not........
  • mencoder Linux CLI video editing how to encode video file into xvid and split by time into multiple parts


    Mencoder is great, you can throw anything at it, including video files from your camera and have it encode into xvid or almost any other format. In my case I took 640x480 video from my Canon and reduced the size by 1/3 with the options below (there are many other options that you can read about in the manual but I like to keep it simple).  Mencoder Encode mencoder <filename.avi> -ovc xvid -oac mp3lame -xvidencopts fixed_quant=4 -o <output.avi>........
  • FUSE/Curlftpfs mount ftp account as drive partition in Linux


    This is a great way to use your ftp server space, for example on your web hosting account (although I believe many hosts don't allow storage like this), but if you have a VPS/Dedicated Server etc.., this would be perfect.  Imagine how easy it is to work with an ftp account that you can just mount as a normal partition or directory in Linux, it would be great for backups etc..   Name curlftpfs - mount a ftp host as a local directory Synopsis........
  • LUKS/cryptsetup Tutorial for Linux Hard Drive Partition Encryption


    This is based on Debian Linux but should apply equally to any *nix distro. Install LUKS/crypt-setup apt-get install cryptsetup Setup your LUKS Partition Of course change /dev/md2 with whatever partition you intend to use LUKS on. cryptsetup --verbose --verify-passphrase luksFormat /dev/md2 You'll be asked to verify your decryption password twice *DO NOT FORGET THIS PASSWORD AS IT IS NOT RECOVERABLE!........
  • Use rcconf to edit startup/init.d/init scripts on Debian/Ubuntu based distributions


    I've never understood how to enable and disable services for different run levels in Debian based distros, it's just weird, annoying and doesn't make sense.  I much prefer chkconfig from RHEL. Just install the package called 'rcconf' and be done with it.  rcconf makes things easy for you. apt-get install rcconf Reading package lists... Done Building dependency tree        Reading state information... Done........
  • Centos How To Add Static Network Route


    route add -net 192.16.5.0 netmask 255.255.255.0 eth0 Of course adjust as you need (eg. the 192.16.5.0 should be changed to the subnet you need access to and eth0 should be changed to the network device that you want that subnet routed through).   I also use the /etc/sysconfig/rc.local script and add the above into it (remember that this route only gets added AFTER all other init scripts have finished though).........
  • How To Set DHCP/Static IP Address in Centos/RHEL/Fedora & Debian/Ubuntu/Kubuntu/MEPIS Set DHCP/Static IP Address


    Basically the two main types of distros are Debian and RHEL/Centos based.  I'm just going to give a quick overview of how the configuration of IP interfaces works in Debian/Centos based distros. *Just one thing to remember, when setting IPs statically you have to manually specify a DNS server in /etc/resolv.conf (since DHCP is what normally does it automatically) Debian/Ubuntu/Kubuntu/MEPIS The IP (DHCP &........
  • CPanel Use /scripts/easyapache to recompile Apache/PHP with different options


    I used the "Image Manipulation and Security Options" and let the script do the rest. /scripts/easyapache For whatever reason, doing a manual compile of PHP myself broke everything and I've never seen that before, that's why I resorted to the cheat of easyapache.........
  • 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


    This is a very simple solution, but most guides out there make you login twice (once to scp the key) and once to put the key in authorized_keys.  There's no need for that.  If you don't already have a ~/.ssh/id_rsa.pub just type "ssh-keygen -t rsa" and keep hitting enter until it's done :) Just use this code to easily enable passwordless login with SSHD key=`cat ~/.ssh/id_rsa.pub`;ssh user@192.168.5.25 "echo $key >> ~/.ssh/auth........
  • Linux 2.6.33.3 Kernel Error CC drivers/message/fusion/mptsas.o drivers/message/fusion/mptsas.c: In function `mptsas_port_delete': drivers/message/fusion/mptsas.c:106: sorry, unimplemented: inlining failed in call to 'mptsas_set_rphy': function b


      CC      drivers/message/fusion/mptsas.o drivers/message/fusion/mptsas.c: In function `mptsas_port_delete': drivers/message/fusion/mptsas.c:106: sorry, unimplemented: inlining failed in call to 'mptsas_set_rphy': function body not available drivers/message/fusion/mptsas.c:462: sorry, unimplemented: called from here make[3]: *** [drivers/message/fusion/mptsas.o] Error 1 make[2]: *** [drivers/message/fusion] Error 2 mak........
  • PDF File Conversion/Solution Using Imagemagick to create PDF files for free, quickly and efficiently


    I'm really starting to love ImageMagick, I've used it to mass convert/resize family photos with scripts and all kinds of handy things. Today I just learned that you can create PDF files with it too, say if you have images scanned or anything else it's very simple: convert *.jpeg output.pdf You can replace jpg with whatever format your files are in.  One thing to remember is that you can specify the order that the images/pages are added to the PDF manu........
  • email2fax and Asterisk to do eFaxing


    It's basically free bash shell script available from: http://wpkg.org/email2fax/index.php/Main_Page Make sure you have the required tools: libtiff ghostscript mpack/munpack Where you can e-mail your Asterisk box and it will fax it to the phone number in the subject line.  The good news ends there, it is fairly undocumented and buggy. Take for example how the documentation mentions you can invoke from the com........
  • 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   ........
  • Compaq V2405CA Laptop - Unixbench Performance Test


    Here are the results, it is Sempron 3000+ AMD Mobile, 500Gig HDD, 512MB RAM with shared ATI Radeon graphics.      #    #  #    #  #  #    #          #####   ######  #    #   ####   #    #    #    #  ##   #  #   #  #&nb........
  • Photoshop Save Layers as a file


    Photoshop Save Layers as a fileJust click: [quote:64c0c64b5a]File: Scripts: Export Layers to Files[/quote:64c0c64b5a] You can choose an individual layer or all of them. Have fun :)........
  • Setup Static IP Address ONBOOT


    Setup Static IP Address ONBOOTAssuming you are using eth0 Note this will work for any version of CentOS and basically any version of Redhat Linux or Redhat based distribution. You would need to create a new file [code:1:02f8d34c30] /etc/sysconfig/network-scripts/ifcfg-eth0:0[/code:1:02f8d34c30] DEVICE=eth0:0 the ":0" at the end specifies alias 0 we could actually change this to ":99" or "........
  • Updated to Version 3.8 and can't login


    Updated to Version 3.8 and can't loginSSHD accepts my password but then hangs at "Last login: Wed Sep 13 21:30:02 2006 from" This occurred during a yum update after upgrading my release, installing the new kernel and rebooting. I got kicked out of sshd after seeing the following during yum update: telnet 100 % done 85/476 tux 100 % done 86/476 ntsysv 100 % done 87/476 rpmdb-redhat 94 % done 88/476........
  • Server Uptime Script


    Server Uptime ScriptA cool and free tool for uptime! http://checkwebsite.org/........
  • Linux Kernel Compilation (Intel(R) 82575/82576 PCI-Express Gigabit Ethernet support ) Error - drivers/net/igb/igb_main.c: In function `igb_up': make[3]: *** [drivers/net/igb/igb_main.o] Error 1


    Linux Kernel v2.6.30.3 102220 blocks   CHK     include/linux/version.h   CHK     include/linux/utsrelease.h   SYMLINK include/asm -> include/asm-x86   CALL    scripts/checksyscalls.sh   CHK     include/linux/compile.h   CC      drivers/net/igb/igb_main.o drivers/net/igb/igb_main.c: In function `igb_up':........
  • Unixbench Score with Glusterfs/Openvz & Quad Core Xeon - Updated with GlusterFS 2.0.8


    You might remember my original GluserFS/OpenVZ benchmark which produced a horrible 29.8 This is the exact same system, but using the latest 2.0.8 (with some small files patch which speeds up performance) you can see it is about 25% faster. I also haven't tuned my config files at all, but there are some settings that should increase performance on small files which I believe i........
  • yum error not working rpmdb: mmap: No such device TypeError: rpmdb open failed


    Loaded plugins: fastestmirror rpmdb: mmap: No such device error: db4 error(19) from dbenv->open: No such device error: cannot open Packages index using db3 - No such device (19) error: cannot open Packages database in /var/lib/rpm 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&qu........
  • 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 HN itself 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........
  • 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.  I checked my /proc/user_beancounters and found this: cat /proc/user_beancounters Version: 2.5 uid resource held maxheld barrier limit failcnt........
  • Bash Script/Linux/Unix HTML/XML Parser


    There is a tool called "xml2" which will parse both HTML and XML scripts, this is very useful to do a mass extraction or conversion of data based on say an HTML table etc.. It becomes even more powerful using bash if certain tags are identified with a certain class="" attribute or something else unique to only the tags you want. Happy parsing.........
  • iPhone Complaint Lock/Standby Disrupts WiFi and uses 3G instead


    Has Apple tried to give a golden egg to the cell phone companies?  Has anyone noticed that if you set your lock time to x minutes, the phone doesn't just lock, it goes into standby.  When it does this, any WiFi connection you have gets dropped and all push/data functions such as e-mail checking are done through the 3G network. There is no way to change this feature and functionality and it's very annoying, especially if you are downloading something or loading files over the........
  • Samba SMB Error - Server not using user level security and no password supplied. tree connect failed: NT_STATUS_WRONG_PASSWORD


    Server not using user level security and no password supplied. tree connect failed: NT_STATUS_WRONG_PASSWORD That happens when trying to use smbclient to connect to a share.  The weird thing is that I can authnenticate just fine from Windows XP. It is partially my mistake, I forgot this share does have a password.  I've tried authenticating with the correct user and also with "Guest" because this works in Windows.  In Linux I ........
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