/ - 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........
  • 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........
  • 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 image convert menu option missing solution


    I already have the caja-image-converter option installed but it shows nothing. Weirdly enough if you install nemo and nautilus converter it does show and work inside caja: The solution is to install *-image-converter sudo apt-get install *-image-converter Reading package lists... Done Building dependency tree       Reading state information... Done Note, selecting 'n........
  • Linux Mint Black Screen after boot no graphics solution


    This is not the normal "black screen" issue and I was shocked to eventually find out why.  The normal advice of reconfiguring Xorg didn't work.  Even booting into "Recovery Mode" did not help. Here is the short end of the stick that fixed it: sudo apt-get install mdm mate-desktop-environment Yes you got it right, mdm and the mate-desktop-environment / gnome were somehow uninstalled.  This must be whe........
  • 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. &........
  • Centos 7 Cudaminer Nvidia setup guide


    I am using a GTX 1060 but replace the download for the driver with the correct/current version for your particular card by visiting: http://www.nvidia.com/Download/index.aspx?lang=en-us   yum install automake curl openssl-devel libcurl-devel gcc gcc-c++ yum -y install kernel-devel-`uname -r` yum -y install unzip #the........
  • Linux Mint 17 How to Enable File Sharing Option in File Manager


    I still cannot understand how this would not be enabled by default and I struggled to find the reason why with manually installing samba etc.. wondering why the option for sharing was not in the menu.   On Linux Mint "MATE" the package is called "caja-share" and on Cinnamon it is called "nemo-share" so edit the below command as necessary: *Also note that the "samba" package is necessary as it is not inst........
  • Cannot Read License File cPanel Solution


    This can happen because port 80 is not open, or your license has expired and/or your IP is out of date and also if the license server itself from cPanel is having issues. In most cases as long as you have a valid license the following command will solve it:  /usr/local/cpanel/cpkeyclt Updating cPanel license...Done. Update succeeded. Building global cache for cpanel...Done   Cannot........
  • CPanel SNI error


    Your server does not support SNI, so all of your SSL websites must use the same SSL certificate. An update to the certificate on an existing SSL website will affect all of your SSL websites, and new SSL websites must use the currently installed certificate.........
  • Virtualbox errors on Ubuntu/Debian/Mint


      The solution was to reinstall the vbox dkms package and do a manual modprobe of the modules it makes. I never sorted out the unable to start due to the USB issue, I did have the guest additions installed but the only way to boot was to change the pointing device from USB to PS2 and then to disable the USB controller (if your pointing device is set as USB, disabling USB will not work because it will re-enable by default when it sees your pointing device is USB, this is w........
  • Installing zoneminder on Ubuntu/Debian Linux Howto


    sudo apt-get install zoneminder [sudo] password for one: Reading package lists... Done Building dependency tree       Reading state information... Done The following packages were automatically installed and are no longer required:   libuser-perl python-evince kdebase-apps kwrite unixodbc   libgnomeprint2.2-data python-soappy vgabios python-metacity hddtemp   python-mediaprof........
  • LVM Tutorial how to create a Physical Volume (PV), Volume Group (vg), and a Logical Volume (LV) within it


    # first we need a physical volume which we use the pvcreate tool to create # I create mine on /dev/sdb3 pvcreate /dev/sdb3   dev_is_mpath: failed to get device for 8:19   Physical volume "/dev/sdb3" successfully created # pvdisplay shows the newly created volume pvdisplay   "/dev/sdb3" is a new physical volume of "1.35 TiB"   --- NEW Physical volume ---   PV N........
  • [Hardware Error]: CPU:0 MC4_STATUS[-|CE|MiscV|-|AddrV|CECC]: 0x9c054c84011c011b [Hardware Error]: cache level: L3/GEN, tx: GEN, mem-tx: RD [Hardware Error]: Northbridge Error (node 0): L3 data cache ECC error.


    This server has been running for weeks without issue, it's currently only using 1 of 2 CPUs as it is running in the office as a test bed (mainly due to the handle 12 bay storage/great for testing HDDs).  The errors below seem to mainly be from AMD CPUs, it's only happened a single time and in the days since I got that error it hasn't occurrred. Interestingly enough /proc/cpuinfo still shows all 4 cores of the CPU (Opteron 2373 Quadcore HE) and the functionality doesn't seem........
  • 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........
  • Openvz "Container is currently mounted (umount first)" solution


    Container is currently mounted (umount first) The container is stuck in the "mounted" state, you must manually start it to get it out of that state (there is no umount option as implied by OpenVZ vzctl).........
  • vzquota : (warning) block_hard_limit [102] < block_current_usage [520824] - Openvz Solution


    vzquota : (warning) block_hard_limit [102] < block_current_usage [520824] This is because your disk usage of the container exceeds the quota. Eg. once on a test container I had accidentally set it to 32MB yet the OS took about 600MB. Just set the quota to something bigger than the currently used space to solve it. vzctl set 3891 --diskspace 5G:5G --save........
  • xen how to resize an image properly


    The best way I could figure out is to use another guest of some sort to do this, while assigning the disk that needs to be resized to the same guest. So say we have /dev/xvda as the guests drive and we've booted it up. We also have /dev/xvdb (this is going to be the image/disk to be resized). In this case it's based on an ext3/4 image. Run e2fsck on it to ensure there are no filesystem errors. e2fsck /dev/xvdb........
  • Xen how to mount disk images off-line and access data


    fdisk -lu VPS.img last_lba(): I don't know how to handle files with mode 81ed You must set cylinders. You can do this from the extra functions menu. Disk VPS.img: 0 MB, 0 bytes 255 heads, 63 sectors/track, 0 cylinders, total 0 sectors Units = sectors of 1 * 512 = 512 bytes      Device Boot      Start         End   ........
  • Ubuntu 10 Nvidia Drivers Not Updated After Kernel Update Solution/How-To Manually Rebuild nvidia kernel modules for Ubuntu


    I dread updating the kernel and rebooting to find the Ubuntu graphics aren't working and you have to manually intervene.   This is usually because Ubuntu for whatever reason didn't update the drivers you need (eg. the manually compiled Nvidia Kernel driver that MUST be recompiled for each and every kernel update unfortunately). The most common reason may be that "linux-source" hasn't been installed automatically on my system.  I tried to manually reinstall the........
  • smart is not smart, it thinks a dead drive is still good


    I had a dying drive that smart thought until it totally disappeared was a good drive, and actually all parameters did look fine but this system was causing my system to lockup and other bad behavior:   === START OF INFORMATION SECTION === Device Model:     WDC WD20EARS-00MVWB0 Serial Number:    WD-WMAZ20139 Firmware Version: 50.0AB50 User Capacity:    2,000,398,934,016 bytes Device........
  • Apache High CPU Usage Enable Mod_Status Guide Solution - Find Cause of High CPU Usage Script/Domain


    mod_status is a great way to track down the source of high CPU usage and to find what vhost/script is the cause of it. It gives you a live view of bandwith usage, CPU usage, and memory usage broken down by domain/vhost and script/URI. Enable mod_status vi /etc/httpd/conf/httpd.conf ExtendedStatus On <Location /server-status> SetHandler server-status Order Deny,Allow Deny from all All........
  • vnstat setup guide/tutorial


    yum -y install vnstat chown nobody.nobody -R /var/lib/vnstat/ #replace venet0 below with your desired interface sudo -u nobody vnstat -u -i venet0 #edit: vi /etc/sysconfig/vnstat #VNSTAT_OPTIONS="-i venet0" # only use the sed below if you are using venet0 instead of eth0 or replace accordingly sed -i 's/eth0/venet0/g' /etc/sysconfig/vnstat   [root@monitor]# yum install vn........
  • 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........
  • Wine stopped working/won't work Solution


    After an upgrade wine wouldn't open anything, not even the pre-installed notepad. There are no wine logs and nothing is mentioned in any standard log file about why. I finally decided to run wine from the shell and see what's going on: wine client error:0: version mismatch 398/402. Your wineserver binary was not upgraded correctly, or you have an older one somewhere in your PATH. Or maybe the wrong wineserver is still running?........
  • 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........
  • 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........
  • Convert HDD/Hard Drive Partition(s) into non-RAID into RAID 1 using existing data without data loss and without reformatting.


    Before we start I take no responsibility for this, you should have a backup and if you make a mistake during this process you could wipe out all of your data.  So backup somewhere else before starting this as a precaution, or make sure it's data you could afford to lose. The RAID 1 Setup (Hardware Wise) I've already setup my 2 x 1TB (Seagate) drives with identical partitions, make sure your new hard drive (the empty one) is setup like your curr........
  • tar gzip: stdout: File too large - Error Size Limit on Large file > 17GB


    The folder I was trying to archive is about 72GB, but much like rsync at about 17GB it chokes because of the filesize.  What's with so many common and essential Linux tools having such limitations?  I guess it is likely that the authors never wrote their code with the idea that files would be so large but it's still very annoying.  It's important to stay on top of these limitations on production servers because I didn't realize what happened until I checked the file with "........
  • XMPP Chat Protocol using Jabber - Guide Tutorial Setup Linux Chat Server


    In Debian based distros: apt-get install jabber Reading package lists... Done Building dependency tree       Reading state information... Done The following packages were automatically installed and are no longer required:   fakeroot dkms Use 'apt-get autoremove' to remove them. The following extra packages will be installed:   jabber-common The following NEW packag........
  • CVSUp the Easy Way


    CVSUp the Easy WayIf you're reading this you probably have never used CVSUp or don't know how. CVSUp can be used for two things or just one if you prefer. *Keeping your kernel up to date *Keeping your port list up to date Start by editing the following file in: [b:76928b387d]vi /usr/share/examples/cvsup/cvs-upfile[/b:76928b387d] It can be quite overwhelming with all the crazy options. Basically there are only 3........
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