/ - 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........
  • 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........
  • 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........
  • Linux Mint 18 Screen Goes Dark or Black After Screensaver or even when using the Desktop Solution


    You can search for this bug and it seems like it may be related to ecryptfs and is many years old. The symptoms are that you return to the computer and the screensaver was active or the screen was asleep/black and it doesn't seem to come back.  But you check by SSH the computer is running fine and are frustrated you'll lose your running programs and have to reboot. There is a simple solution: Ctrl + Alt + F1 Ctrl + Alt + F8 Ba........
  • [Wed Sep 20 15:34:44 2017] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec) [Wed Sep 20 15:34:44 2017] [error] Init: Unable to read server certificate from file /www/ssl-certs/server.crt [Wed Sep 20 15:34:44 2017] [error] SSL Library Err


    [Wed Sep 20 15:34:44 2017] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec) [Wed Sep 20 15:34:44 2017] [error] Init: Unable to read server certificate from file /www/ssl-certs/server.crt [Wed Sep 20 15:34:44 2017] [error] SSL Library Error: 218529960 error:0D0680A8:asn1 encoding routines:ASN1_CHECK_TLEN:wrong tag [Wed Sep 20 15:34:44 2017] [error] SSL Library Error: 218595386 error:0D07803A:asn1 encoding routines:ASN1_ITEM_EX_D2I:nested asn1 error........
  • vbulletin 4.2.5 after upgrading from 3.6 white screen fatal php errors


    The code may lead you to believe you have an incompatible template but if you are not trying to use an old template currently that is not the issue.  I actually deleted all 3.x style templates to make sure. What the issue is, is old plugins that are not compatible but Vbulletin does not seem to account for this except that you'll see a fatal PHP error.  You should disable all plugins and then enable one by one until you find the one that is causing the issue. &........
  • l2tp ipsec VPN Error Sep 12 18:16:25 vps pluto[7299]: ERROR: asynchronous network error report on eth0 (sport=500) for message to 192.5.6.2 port 20640, complainant 192.5.6.2: Connection refused [errno 111, origin ICMP type 3 code 3 (not authenticated


    Sep 12 18:16:25 vps pluto[7299]: ERROR: asynchronous network error report on eth0 (sport=500) for message to 192.5.6.2 port 20640, complainant 192.5.6.2: Connection refused [errno 111, origin ICMP type 3 code 3 (not authenticated)] Some say changing the "leftprotoport=17/%any" will fix this but I have not found this to be the case. Essentially it means at least one end is blocking the ipsec packets.  Sometimes the %any allows an alt........
  • 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              ........
  • 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........
  • 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 Mint Install Netboot PXE Guide Howto


    *Update so this doesn't work it must be something to do with the path of nfs or something else but the installer fails with "Installer crashed" at the end whereas with the CD/USB it works. This assumes you've already installed and configured a separate PXE/DHCP server somewhere else and your /tftpboot directory is setup. This is for Linux Mint 18.1 but generally applies to most versions although you may have tro change things like "casper"........
  • sed how to avoid escaping


    sed gets to be a pain and a real mess and is hard to read and understand when you have to escape things like / etc. I did not realize until recently that you don't need to use / as a separator, you can use virtually any non letter or number character. Eg we have used # as the separator to avoid having to escape the forward slashes and in this way the command is plain, easy to understand, edit and saves time/hassle without the need for escaping. sed -i s#http........
  • ECC Errors in action


    Message from syslogd@server at Sep 14 11:35:59 ...  kernel:[Hardware Error]: MC4 Error (node 1): DRAM ECC error detected on the NB. Message from syslogd@server at Sep 14 11:35:59 ...  kernel:[Hardware Error]: Error Status: Corrected error, no action required. Message from syslogd@server at Sep 14 11:35:59 ...  kernel:[Hardware Error]: CPU:6 (10:8:0) MC4_STATUS[Over|CE|MiscV|-|AddrV|CECC]: 0xdc00400021080813........
  • bash Linux basename and directory name, get the actual directory and file


    Example: basename /var/log/messages messages As shown above the "basename" utility gives you the end filename separately.   dirname /var/log/messages /var/log As shown above the "dirname" utlity gives you just the utility even if you pass it a specific file. The above two utilities are very helpful in Bash scripting when working with files and directories co........
  • strange kernel dmesg errors


    Sep 26 16:56:21 box kernel: 00 00 00 00 00 00 00 00 Sep 26 16:56:21 box kernel: [37007.155690]   d_alias libdl-2.12.so d_count=9 d_flags=8 Sep 26 16:56:21 box kernel: [37007.155697] 09 00 00 00 08 00 00 00 9f 05 9f 05 00 00 00 00 c0 71 1d 18 04 88 ff ff 00 00 00 00 00 00 00 00 a0 7e 48 00 00 c9 ff ff 78 a9 21 18 04 88 ff ff 3a 7b fa 4e 0d 00 00 00 98 5c 2d 18 04 88 ff ff 18 5c 2d 18 04 88 ff ff 18 5c 2d 18 04 88 ff ff 00 01 10 00 00 00 ad de 00 02 20 00 00 00 ad de f8........
  • 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........
  • 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........
  • 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........
  • Ubuntu 9.04 Crash


    CPU/Kernel/MB/RAID problem? Jan  5 12:45:05 testbox kernel: [653298.890004] BUG: soft lockup - CPU#0 stuck for 61s! [hal-acl-tool:4168] Jan  5 12:45:05 testbox kernel: [653298.890005] Modules linked in: vmnet vmci vmmon binfmt_misc drbd video output input_polldev ocfs2_stackglue ocfs2_dlmfs ocfs2_dlm ocfs2_nodemanager configfs k8temp hwmon_vid lp snd_hda_intel snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_dummy snd_seq_oss snd_seq_midi snd_rawmidi........
  • SSH delay problem UseDNS and disabling GSSAPI does not help


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


      Create New RAID 1 Array: First setup your partitions (make sure they are exactly the same size) In my example I have sda3 and sdb3 which are 500GB in size. mdadm --create /dev/md2 --level=1 --raid-devices=2 /dev/sda3 /dev/sdb3 mdadm: array /dev/md2 started. Check Status Of The Array *Note I already have other arrays md0 and md1. You can see below that md2 is syn........
  • 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........
  • 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........
  • 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........
  • 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........
  • 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........
  • Viewing and Connecting to an SMB Samba Share on Windows/Linux/Unix


    This will give you the basic info needed to browse and connect to Samba shares from the command line.  From the GUI of Gnome or KDE etc, it is pretty standard and straight forward.  However, I've found very little guides on how to do it from the command line and if you're like me, a nerd who prefers command line for its simplicity and for remote use, this is the way to go. First get a list of all the Samba/SMB shares on the target. smbclient -L hostname........
  • Latest Articles

  • syntax error, unexpected T_SL in PHP Solution
  • grep regular expression match number range between specific numbers
  • bash how to print out lines of text within a range from the first occurrence
  • bash script how to to check LAN computers for open ports
  • MySQL Using mytop Debug Source of High IO and Slow Performance
  • How To Mathematically Convert and Calculate Binary Value To Decimal Value
  • systemd management using systemctl and journalctl to check systemd logs
  • css how to format code in the code tag
  • css br with extra blank line
  • What is /dev/pts and why do we need it in Linux?
  • Linux What is umask (user mask) for file and directory creation permissions and how to calculate umask and change the defaults
  • Linux Permissions and Groups Real Usecase for Group Access
  • Centos 7 python34 how to install the gi library
  • Centos 7 - Convert Minimal to Graphical GUI GNOME or KDE Desktop
  • AMD Set Fan Speed and Other Powerplay Memory/CPU Timings with a Linux script
  • Ethereum Mining Claymore Nanopool Error
  • genisoimage errors with long filenames and deep directory structures
  • Linux Kernel USB Export Errors
  • How to download gajim 0.16.9 XMPP/Jabber client so you can use OMEMO encryption
  • HP DL385 G7 Linux BIOS Update Flash