/ - rtt - IT Resource

  • Centos 7 - Convert Minimal to Graphical GUI GNOME or KDE Desktop


    Did you just install the minimal version by accident or want to install the GUI?  No need to reinstall just tell yum to do the work for you! You could actually have both installed and choose one as your preference on demand (although many people prefer GNOME's simplicity). Step 1.) Install Gnome and/or KDE. To install the GNOME Desktop on Centos 7: yum -y groups install "GNOME Desktop" To........
  • Linux Mint/Ubuntu/Debian Nvidia driver becomes slow graphics performance issue


    I've had this issue since Ubuntu 9 and now even on Linux Mint 17 no matter what latest version of the Nvidia proprietary driver that I use.  It just becomes slower and slower and only gets better after rebooting or restarting Xorg. Someone here has it as well https://askubuntu.com/questions/822449/graphics-becomes-slow-after-a-while/917886 It's very fru........
  • SELinux targeted policy relabel is required


    You may get this after a long time of not rebooting but especially if you have rsync'd a / partition or deployed an image to another VPS or computer, you will often have this issue. The good thing it usually just takes a reboot. Here is more info from Centos........
  • iptables: Applying firewall rules: iptables-restore: line 40 failed


     service iptables start  iptables: Applying firewall rules: iptables-restore: line 40 failed                                                            [FAILED]........
  • Lost connection to MySQL server during query [2013]


    This happened while trying to delete several thousand users from phpBB and basically corrupted the innoDB tables. InnoDB: Page lsn 3 881164362, low 4 bytes of lsn at page end 881164362 InnoDB: Page number (if stored to page already) 86920, InnoDB: space id (if created with >= MySQL-4.1.1 and stored already) 0 InnoDB: Page may be an index page where index id is 700 InnoDB: (index "tid_post_time" of table "phpBBdb2005"."phpbb3_p........
  • ResourceManager[31705]: CRIT: Resource STOP failure. Reboot required!


    ResourceManager[31705]: CRIT: Resource STOP failure. Reboot required! This happened on a cluster I am running with heartbeat for no particular reason that I can figure out. The box ended up rebooting itself for some reason.  It was not a big deal in the sense that the other servers in the cluster kept running but it would be nice to find the cause of this.........
  • sysctl how to apply values from /etc/sysctl.conf after changes


    If you make changes to /etc/sysctl.conf (which are permanent and not lost during reboot) but want them to apply with rebooting just use the following command: sysctl -p After that your changes will be enabled.........
  • 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........
  • vino crashed/stopped working, restart vino manually without rebooting


    The normal solution would be as follows: export DISPLAY=:0.0 /usr/lib/vino/vino-server & But what happens if that doesn't work?  I haven't been able to find much documentation about how to find the list of displays and how their numbering works in Xorg. Sometimes you'll get this error when trying to restart vino: Cannot open display: For some reason my display is not on 0.0........
  • ifup eth0 SIOCSIFFLAGS: Cannot allocate memory Failed to bring up eth0 Centos Network won't work after kernel update and reboot


    ifup eth0 SIOCSIFFLAGS: Cannot allocate memory Failed to bring up eth0 This is on a Centos 5.5 machine with OpenVZ kernel 2.6.18-238.12.1.el5.028stab091.1PAE, I updated 3 systems with the same hardware to the same kernel and for some reason the network didn't come back. This only happened once the first time I booted into the new kernel and hasn't happened again but this is a serious issue for those running systems from remote locations such as a datacente........
  • Nautilus/GNOME/Ubuntu File Manager not applying appearance style/changes


    I thought it was a GNOME problem because no matter what styles I applied Nautilus wouldn't change, but it was only Nautilus that wouldn't change/update anymore so I should have known. The only fix/solution I knew of other than rebooting is the following: sudo killall nautilus I tried closing all instances of nautilus that were visible and it had no effect. And another thing to remember is that only will appearances/styles/themes not apply to N........
  • md: kicking non-fresh sda1 from array! - fix/solution


    md: Autodetecting RAID arrays. md: autorun ... md: considering sdb1 ... md:  adding sdb1 ... md:  adding sda1 ... md: created md0 md: bind<sda1> md: bind<sdb1> md: running: <sdb1><sda1> md: kicking non-fresh sda1 from array! md: unbind<sda1> md: export_rdev(sda1) raid1: raid set md0 active with 1 out of 2 mirrors The md0 raid kicked sda1 ou........
  • Fix Slow 2D Graphics Xorg.conf Ubuntu/Debian/Mandriva Linux


    I'm using Ubuntu 8.04 but anyone using older kernels will find this may apply to them.  My Intel graphics are very slow with the default Xorg settings but by using "EXA" acceleration, scrolling down windows of text becomes pretty snappy. Just edit /etc/X11/xorg.conf Section "Device"         Identifier      "Configured Video Device"   &nb........
  • Gigabyte GA-H57M-USB3 Complaint Review/Comments


    I'm not impressed with this motherboard, I was impressed with my Gigabyte AM3 board which seems to work flawlessly. Everyone knows that the firmware is flawed, even though I have the F6, it still seems that the system doesn't reset properly or quickly enough. Another HUGE problem is that in most Linux kernels the NIC won't work (if you try 10 times by rebooting it might).  I also notice that you need to power down for it to work. This board does not seem very com........
  • Asus Eee PC 1000HE Crashed/Need To Recover/Restore Windows? Easy Solution is Hitting F9


    I'm not a fan of Asus and won't be buying another because of having to fight Asus over a bogus warranty denial (it's a long story but they only replied about how to RMA my unit weeks later on the EXACT day the warranty expired). Anyway, it's just a matter of hitting F9 to do this, there's no need to worry about booting from USB or CD (unless of course you want a different OS eg. Windows XP Pro, Vista/7, or a flavor of Linux or Unix).  Also remember that you need to fully/properl........
  • Linux AHCI Hotswap Tips - Remember To Reread The Partition Table WITHOUT rebooting


    From the package "parted" you can use the command "partprobe" to re-read the partition table.  I really hate rebooting, and that's what I loved to hear about AHCI motherboards, that they allow hotswap so you don't have to reboot.  But that's only as good as the OS, if the OS does not reload the partition table you won't be able to do anything with that new drive you attached without rebooting.  Yes, even without re-reading the partiton table Linux will........
  • 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........
  • Linux Kernel Error (2.6.33.1) BUG: Bad page state in process swapper - Keeps rebooting - initramfs bug


    *This is a bug with initramfs support, all kernels after around 2.6.27.54 suffer from this problem. If you try to include initramfs into your kernel (I mean actually building your binaries into the kernel) this will always happen. Obviously some code has changed in recent kernels that is present in all new kernels, it makes it impossible to boot I've tried the latest 2.6.32, 2.6.33, 2.6.34, 2.6.35, 2.6.36, 2.6.37, 2.6.38 kernels and they all do this.  I found one bug re........
  • SIOCSIFADDR No such device eth0 error while getting interface flags - eth0 Ethernet Device can


    I got this after copying a VMWare image onto another machine in Debian. SIOCSIFADDR No such device eth0 error while getting interface flags The solution 1.) Find and edit the device line in persisent-net.rules note it will be prefixed with something like z25 or something else. vi /etc/udev/rules.d/z25_persistent-net.rules The easiest way is to comment anything out. If you are feeling........
  • 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 ........
  • Latest Articles

  • How Does Cisco CUCM (Cisco Unified Communication Manager) Work?
  • What DNS Options Does Active Directory Offer in Windows Server 2008,2012,2016 ?
  • 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