Computer in Linux won't boot and goes to initramfs busybox Solution

This is mainly for if you've done something silly like trying to clone a Live, running VM image. In this example, the VM initially finds grub and tries to boot but is kicked straight into initramfs rescue mode/busybox right after this. If you've done this "silly" thing, you could have dataloss but a lot of times just using fsck will fix it as you are guaranteed at best to have some corruption and inconsistencies in the filesystem. My theory is that some files wer........

How to kill a docker swarm

Assign way more replicas than you have of memory on all nodes and watch the Swarm crash which can easily reproduce in a small VMfor testing. root@Deb11Docker01:~# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAM........

Linux how to get list of all timezones on system Ubuntu

find /usr/share/zoneinfo/|sed s#"/usr/share/zoneinfo/"##g|grep "/"|grep -v posix|grep -v ^"Etc/"|grep -v ^right|grep -v ^"SystemV" Africa/Addis_Ababa Africa/Abidjan Africa/Blantyre Africa/Lusaka Africa/Casablanca Africa/Libreville Africa/Asmara Africa/Bujumbura Africa/Dakar Africa/Lagos Africa/Malabo Africa/Harare Africa/Kigali........

How To Upgrade Debian 8,9,10 to Debian 12 Bookworm

Step 1.) Upgrade to Debian 11 first The process to go to Debian 12 is not as smooth as 11, when trying to upgrade from Debian 10. In fact, it doesn't work directly, so you'll first need to follow this guide to update to Debian 11, reboot and come back here if successful. Step 2.) Update sources.list Update your /etc/apt/sources.list like this: deb http://........

How to use the FTDI USB serial cable to RJ45 adapter to connect to the console on Cisco/Juniper Switch Router Firewall in Linux Ubuntu Debian Redhat

This should work for most console ports of other manufacturers too. It is a quick and simple method for emegencies or deploying a few appliances/devices in a non-standard environment or small environment. However, if this is a route thing, or the equipment is not physically close to you, it would be best to use some sort of "Terminal" server which is an IP connected switch with several serial ports built-in for this purpose. Normally they accessible by web/........

kernel panic initramfs not syncing cause solution

Check your initramfs if it's missing /dev/null or /dev/console, this is likely the reason. If you want all actual devices to be created you could also enable devtmpfs in your kernel (.config) and mount like this during init: CONFIG_DEVTMPFS=y CONFIG_DEVTMPFS_MOUNT=y mount -t devtmpfs none /dev But note devtmpfs will not create /dev/null or /dev/console for........

RHEL 8 CentOS 8, Alma Linux 8, Rocky Linux 8 System Not Booting with RAID or on other servers/computers Solution for dracut and initramfs missing kernel modules

This seems to have changed for RHEL 8 where a normal dracut to update your initramfs creates a system that only boots for the running kernel. For example if you have Kernel 5 and then chroot into a RHEL 8 variant which uses kernel 4.18, and run dracut, it seems that by default the system will be unbootable. It is also the case that if you move your RAID array or drives to another server that it will be unbootable, because dracut seems to only include modules needed for the curre........

Ubuntu Debian Mint Linux How To Update Initramfs Manually update-initramfs

The easiest way for the current running kernel is: update-initramfs -u -k `uname -r` You could change -k to a specific kernel name if for some reason the current is not running (eg. if you are chrooted or in recovery mode). If you want to update all kernels then use "-k all" update-initramfs -k all -u update-initramfs: Generating /boot/initrd.img-5.4.0-162-generic........

CentOS 7 / 8 cannot boot with with mdadm RAID array solution

This article about migrating to a CentOS 7 /8 RAID mdadm array has a lot of info but I wanted to focus specifically on what newer versions of CentOS 7 require to boot mdadm and what changes are necessary on CentOS 7.8+ CentOS 7 / 8 mdadm RAID booting requirements This assumes you are chrooting into an existing install or using it to get a new deployment ready. However, these steps can........

i915 nouveau Nvidia GPU not starting lightdm Xorg failing solution for Could not determine valid watermarks for inherited state

It may appear to be an Xorg or lightdm/gdm/mdm error but in reality for many users with this issue, it's a driver conflict and issue. I had a system that had two GPUs, an Intel and Nvidia GPU. The only thing that got it working was to remove the nouveau driver and blacklist it so it never came back, then the Intel GPU works fine without these issues. Solution sudo rmmod nouveau add nouveau/other driver to blacklist edit th........

HongKong VPS Server, Cloud, Dedicated Server, Co-Location, Datacenter The Best Guide on Hong Kong, China Internet IT/Computing

In our 2024 VPS Server/Cloud Buyer's Guide, we place the location of your VPS/hosting/server as one of the priorities that is often overlooked. 2024 Update - Datacent........

Ubuntu/Debian Linux/Unix Howto Setup Install Syslinux Bootable USB with EFI and MBR from Command Line/CLI Terminal

There aren't too many simple guides that show you how to use commands to setup your USB or other drive as a normal bootable drive where you can easily boot custom kernels or whatever OS you would like. 1. Get the tools we need: We install "syslinux" for MBR and "syslinux-efi" for EFI and "MBR" as we need a tool that embeds the actual MBR into our USB: sudo apt install syslinux syslinux-efi mbr........

EFI PXE grub2 Howto guide for Linux EFI PXE Booting on Debian, Mint, Ubuntu, RHEL

Just a quick note and warning is that if you are testing to see if EFIPXE booting works on a VM, MAKE SURE it actually works. For example Iinitially tested using my Distro's QEMU 2.5+dfsg-5ubuntu10.46 and ovmf BIOS firmware (OVMF supports EFI). However, I found on old versions of QEMU (like 2.5), EFIbooting with GRUB NEVER works so it may appear that you have made a mistake when everything is fine when you boot a physi........

CentOS 7 8 PXEBoot Netinstall Not Working Solution "Pane is dead "new value non-exisetnt xfs filesystem is not valid as a default fs type"

The problem seems to be that whatever kernel and initrd you have is tied to an old version of CentOS 7 that is no longer in the current repos of most mirrors. If you were previously able to PXEboot and install CentOS and you are sure your network and tftp are good the problem is that you have an outdated kernel and initramfs that point to a defunct version.........

Scanner not working in Linux Ubuntu Fedora Mint Debian over the network? Use sane-airscan!

I have a Canon MF642c and the scanner wouldn't work. I tried to use saned but it didn't work with the BJNPlike it did for some other Canon models. Introducing sane-airscan with packages for the most common distributions: https://software.opensuse.org/download.html?project=home%3Apzz&package=sane-airscan http........

How To Install python 3.4 3.5 and up on Linux with wine - Working Solution

This is sure simple if you follow the guide but it took a lot of hacking around to make this work on Debian/Ubuntu! Now before you ask why bother running wine and python, the reason is because Python executables are NOT cross-platform. If you run pyinstaller in Linux, that binary will only run on Linux and the same if you do it in Windows. So it is preferable if you have a single environment that you can create Linux and Windows binaries from rather than running 2 separate........

OpenVZ vs LXC DIR mode poor security in LXC

It is unfortunate that LXC's dir mode is completely insecure and allows way too much information from the host to be seen. I wonder if there will eventually be a way to break into the host filesystem or other container's storage? OpenVZ better security: [root@ev ~]# cat /proc/mdstat cat: /proc/mdstat: No such file or directory /dev/simfs 843G 740G 61G........

Howto Set Static IP on boot in initramfs for dropbear or other purposes NFS, Linux, Debian, Ubuntu, CentOS

This is only really necessary in the case you don't want DHCP. If you are dealing with an encrypted LUKS server on the internet, you will often want to have a static IP so you know which IP to connect to (or if you have a semi-static IP assigned by DHCP). SET IP Address by /etc/initramfs-tools/initramfs.conf IP Address=192.168.1.27 Gateway=192.168.1.1 Subnet Mask: 255.255.255.0 Hostname=myhome.com IP=192.1........

Convert and install to LUKS Encrypted Drive Ubuntu 18.04 19.10 Linux Mint and Debian Based Linux

The reason for doing this is that the installer doesn't seem to work properly for LUKS and the server installer doesn't even support LUKS anymore. When you use the GUI install on Desktop for LUKS it won't boot and will just hang after you enter your password. So the only reliable way is to do it ourselves. 1.) Make a default minimal install of Ubuntu 2.) Have a secondary disk on the server or VM. 3.)........

CentOS 8 how to convert to a bootable mdadm RAID software array

The cool thing here is that we only need 1 drive to make a RAID 10 or RAID 1 array, we just tell the Linux mdadm utility that the other drive is "missing" and we can then add our original drive to the array after booting into our new RAID array. Step#1 Install tools we need yum -y install mdadm rsync Step #2 Create your partitions on the drive that will be our RAID array Here I assume it is /dev........

ADATA USB Thumb Drive Issues

This is the reason that I don't like the new ADATA USB drives such as the UV128/64GB or 128GB drives and other ones that look to be the same style (the green sliding USB connector). They just don't work well from new and never work properly at any point. [ 788.242463] usb 1-1.2: new high-speed USB device number 16 using ehci-pci [ 788.339816] usb 1-1.2: New USB device found, idVendor=125f, idProduct=db8a [ 7........

Ubuntu Debian Linux Mint r8169 r8168 Network Driver Problem and Solution

This problem has been around forever, Linux seems to think it is fine to use the r8169 driver for an r8168 NIC but this often causes problems including the link not working at all. In my case ethttool shows the link up and detected but it simply does not work especially on a laptop that has been resumed from suspension. Sometimes it takes several minutes for it to work or to unplug and replug the ethernet. Here is the solution: Install th........

Debian Ubuntu and Linux Mint Broken Kernel After Date - New Extra Module Naming Convention

I don't consider a lot of these "extra" kernel modules "nice to have" as they often contain drivers for essential items like your soundcard, your NIC and many other devices that may not work. Sometimes you may find that "sound" or "ethernet" worked before a kernel/OS upgrade and now in the new version they don't. Often it will be because you need to install the "extra" kernel modules. One other weird thing is that sometimes........

Linux wlan0 check all wireless clients

iw dev wlan0 station dump This is very useful because it is helpful if you are running something like hostapd and need to see the signal strength and negotiated connection speed. Station ff:ff:ff:ff:ff:ff (on wlan0) inactive time: 16309 ms rx bytes: 25451 rx packets: 325 tx bytes: 44381 tx packets: 159 tx retries: 0 tx failed: 0 signal: -72 [-72] dBm signal avg: -72 [-72] dBm........

Linux Kernel USB Export Errors

4.374647] usb_common: exports duplicate symbol usb_get_dr_mode (owned by kernel) [ 4.403334] usbcore: exports duplicate symbol __usb_get_extra_descriptor (owned by kernel) [ 4.427736] xhci_hcd 0000:00:15.0: xHCI Host Controller [ 4.427844] xhci_hcd 0000:00:15.0: new USB bus registered, assigned bus number 1 [ 4.429040] xhci_hcd 0000:00:15.0: hcc params 0x200077c1 hci version 0x100 quirks 0x01109810 [ 4.429141] xhci_hcd 0000:00:15.0: cache line size of 64 is not sup........

VMWare ESXi 6.7 SSH/PowerShell CLI Commands

[root@localhost:~] BootModuleConfig.sh echo host-ind nfcd........

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 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........

Linux Mint Ubuntu Debian How To Disable Webcam Automatically Onboot To Prevent Spying and Privacy Violations

It is well known hackers, the NSA, CIA and other groups have created malware to secretly turn on your webcam and microphone on your phone, tv etc.. But fortunately on our computers and laptops we have some options. Most webcams use the "uvcvideo" kernel module / driver. You can disable this in two ways on boot. I recommend both just as a failsafe. Disable it on rc.local once your system boots automatically Add the followi........

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: ........

Centos 6.6/6.9 KVM VM Kernel Panic On Boot - Kernel panic - not syncing: Attempted to kill init!

Iam not sure why this is happening neither the hostnode or VM changed. All I did was reboot the hostnode and startup the Centos VM again, also note it happened with the original kernel on the VM and also the latest 6.9 kernel as of this writing as shown below. Host Node: Centos 6.9 Kernel:2.6.32-696.6.3.el6.x86_64 Kernel: 2.6.32-042stab123.9 Same result in any kernel above........

[1035724.274610] [drm:intel_pipe_update_end [i915_bpo]] ERROR Atomic update failure on pipe A (start=62076478 end=62076479) time 102 us, min 894, max 899, scanline start 893, end 900 W: Possible missing firmware /lib/firmware/i915/kbl_dmc_ver1.bin

[1035724.274610] [drm:intel_pipe_update_end [i915_bpo]] *ERROR* Atomic update failure on pipe A (start=62076478 end=62076479) time 102 us, min 894, max 899, scanline start 893, end 900 W: Possible missing firmware /lib/firmware/i915/kbl_dmc_ver1.bin for module i915_bpo I've been getting those errors on a J3455 NUC box with the latest kernel on Linux Mint 18.2. When updating the initramfs I also got the error about the firmware........

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 ........

How to extract view contents of initramfs image gzip'd

Very simple browse to your /boot directory It does make more sense to extract the image in its own directory eg "initramfs-blabla-dir" as it will literally extract directly to the pwd. cp initramfs.img someotherdir cd someotherdir zcat initramfs-3.10.0-514.el7.x86_64.img | cpio -idmv........

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! If you have trouble booting after this check this CentOS mdadm RAID booting/fixing guide. One huge caveat if you are an oldschool user or sysadmin who has avoided UEFIbooting The nor........

USB 3.0 External HDD Enclosure Seagate UAS problems - [sdd] tag#1 CDB: Write(16) 8a 00 00 00 00 01 70 04 08 68 00 00 00 08 00 00

This is a 8TB Seagate external USB 3.0 device apparently newer kernels use a module called "UAS" instead of "USB Storage" which causes issues as a lot of devices are not properly supported in UAS mode by the kernel driver. The solution some say is to disable UAS specifically for your USB device but I'd rather just disable UAS altogether. Solution blacklist UAS: *do not do this it does not work and just causes your USB 3.0........

USB Device/MP3 Player not working properly and can't browse the device filesystem? Check the cable twice and again!

Here is a simple MP3 player and now there's a reason to understand why the supplied cable has some kind of capacitor and is very short. These devices can be VERY finicky and any voltage fluctuation or difference is enough to cause issues. Take for example the error messages from Linux Mint: [804829.895414] usb 1-1: USB disconnect, device number 11 [806961.109030] usb 1-1: new high-speed USB device number 12 using xhci_hcd........

Migrating from Linux Mint 17.2 mdadm RAID array to a new one (because I upgraded to larger drives).

1.) Replicate the number of partitions in your new drives. gdisk /dev/sda gdisk /dev/sdb I created 3 partitions of the same same size. partition #1: +1G (/boot) partition #2: +60G (swap) partition #3: rest of it (/) #note if you are using GPT/gdisk you need to create separate a partition at least 1MB in size (in my case I would a 4th partition and mark it type ef02).........

mdadm: CREATE group disk not found Incrementally started RAID arrays. Incrementally starting RAID arrays...

mdadm won't boot in Ubuntu/Mint/Debian anymore. You just get the following in a loop: mdadm: CREATE group disk not found Incrementally started RAID arrays. Incrementally starting RAID arrays... mdadm: CREATE group disk not found Incrementally started RAID arrays. Incrementally starting RAID arrays... mdadm: CREATE group disk not found Incrementally started RAID arrays. Incrementally starting RAID arrays... mdadm: CREATE group dis........

mdadm change wrong device name md127 fix and solution in Linux

md127 issue, it should be /dev/md3 per mdadm.conf Any time something is mounted as md127 it almost always means there is no entry for this mdadm array in the mdadm.conf in initramfs (which is separate from your actual /etc/mdadm.conf). cat /etc/mdadm.conf ARRAY /dev/md3 metadata=1.2 UUID=b6722845:381cc94e:7a2c5b5f:8e3b7c4f The reason for this is something strange, most Linux OS's bizarrely always keep their own copy of /etc/mdadm.con........

OpenVZ Migration Hostnode Containers from Centos 5 to Centos 6

migrating from an old OpenVZ (Centos 5) to new OpenVZ (Centos 6) Also if migrating from 32-bit HN to 64-bit your RAM will probably be much bigger than it should be! 16x bigger eg. 32bit HN: total used free shared buffers cached Mem:&nb........

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........

How to root and unlock S4 in Canada Bell/Rogers/Telus/Fido I337 4.4.2

i337 Canada on Bell is hard to root or even install TWRP Installed TWRP from Odin and my computer gave me the bluescreen at the end but it seemed to be successful (after ODIN said reset). TWRP mode does not seem to enter, instead you get the Android recovery mode with Volume up + Home http://galaxys4root.com/galaxy-s4-root/how-to-root-att-or-verizon-galaxy-s4-on-android-4-4-2/ 1.)........

OpenVZ Howto disable ploop and switch back to SIMFS

It's simple, just edit /etc/vz/vz.conf and add or change the following: VE_LAYOUT=simfs........

mytop install errors

mytop-1.4-2.el5.rf.noarch from rpmforge has depsolving problems --> Missing Dependency: perl(DBI) is needed by package mytop-1.4-2.el5.rf.noarch (rpmforge) solution: #disabling excludes is required on CPanel type boxes which exclude most updates including perl-DBI yum --disableexcludes=main install perl-DBI mytop-1.4-2.el5.rf.noarch from rpmforge has depsolving problems --> Missing Dependency:........

yum error "Error: database disk image is malformed" solution

yum -y install mathtools Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: centos.mirror.rafal.ca * epel: mirror.steadfast.net * extras: mirror.agmn.ca * rpmforge: repoforge.mirror.constant.com * updates: centosb5.centos.org extras ........

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........

yum Centos 386 and 64 bit conflict resolution

This can happen when you install RPMForge or other repos with the wrong architecture and here's how you fix it (simply uninstalling won't usually fix it): solution yum clean all yum -y install openvpn Loaded plugins: fastestmirror, presto Loading mirror speeds from cached hostfile * base: mirror.its.sfu.ca * extras: centos.mirror.nexicom.net * rpmforge: mirror.cpsc.ucalgary.ca * up........

yum error installing php solution - exclude php from being installed from third party repos

Error: Package: php-Monolog-dynamo-1.7.0-1.el6.noarch (epel) Requires: php-aws-sdk Error: php-pecl-zendopcache conflicts with 1:php-eaccelerator-0.9.6.1-1.el6.x86_64 Error: php-xcache conflicts with php-pecl-apc-3.1.9-2.el6.x86_64 Error: php-pecl-zendopcache conflicts with php-pecl-apc-3.1.9-2.el6.x86_64 Error: Package: php-horde-Horde-Vfs-2.1.2-2.el6.noarch (epel) &n........

Centos Howto Upgrade to PHP 5.3 from 5.2

It's not as simple as "yum install" as you can see below and it doesn't stop there. yum install php53 Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * rpmforge: mirror.us.leaseweb.net * extras: centos.mirror.rafal.ca * updates: centos.mirror.nexicom.net * base: centos.mirror.nexicom.net * addons: centos.mirror.nexicom.net Setting up Install Process........

rpmforge Centos 6 how to install

rpm --import http://apt.sw.be/RPM-GPG-KEY.dag.txt i686: rpm -ivh http://packages.sw.be/rpmforge-release/rpmforge-release-0.5.2-2.el6.rf.i686.rpm x64: rpm -ivh http://packages.sw.be/rpmforge-release/rpmforge-release-0.5.2-2.el6.rf.x86_64.rpm ........

Centos 5,6,7 Install EPEL from Fedora for extra packages Howto

http://fedoraproject.org/wiki/EPEL#How_can_I_use_these_extra_packages.3F Visit the above URL, choose your version and architecture and install it. EPELhas a lot of missing and extra packages that rpmforge does not. For old versions of EPEL that are deprecated, eg.........

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........

rpmforge Centos 6 x64 howto install

rpm --import http://apt.sw.be/RPM-GPG-KEY.dag.txt rpm -ivh http://packages.sw.be/rpmforge-release/rpmforge-release-0.5.2-2.el6.rf.x86_64.rpm Retrieving http://packages.sw.be/rpmforge-release/rpmforge-release-0.5.2-2.el6.rf.x86_64.rpm Preparing... ########################################### [100%] 1:rpmforge-release #############........

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 ........

kvm cannot boot xen guest using lvm

This booting error is because the Xen PV guest image uses the Xen kernel, this is not compatible with anything but a host running a Xen kernel. I did a kpartx -av virtual.img and then it created some partitions that showed up in fdisk. I mounted it and did a chroot into it and removed the xen kernel and installed a normal kernel but Xen still shows the same kernel in Grub (only the Xen one). This is strange but it seems like this Xen PV guest has some sort of hidden or........

Centos how to upgrade from PHP 5.2 to 5.3 without downtime

This may sound silly but there will be conflicts/issues with the default Centos repository so you have to use a third party like remi (I prefer not to do this but it's the only option unless you migrate your sites/data to another server or can stand some downtime-not an option IMHOon a production server). You may need to upgrade to PHP5.3 to run Joomla or many other reasons. Your host needs to use PHP 5.2.4 or higher to run this version of Jo........

Xen non-HVM container won't work/boot anymore

One of my test Centos 5 containers was on a partition that filled up and it threw all sorts of errors and stopped responding but now I can't boot it again anymore. All the console shows is the Linux Penguin on the top left corner and the xm console says "usbcore: registered new driver hub" and has halted there. Centos 5 Xen container stuck/frozen won't boot on "usbcore: registered new driver hub" Another great way of troubleshooting is booting fro........

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........

rpmforge: [#### ] 471/10722Segmentation fault yum[18934]: segfault at 0000000000000000 rip 00002ade62153a30 rsp 00007fff76f9fe58 error 4

A few days ago this happened on multiple Centos 5 servers and apparently anyone using rpmforge was affected by this error and there was no solution other than disabling that repo to fix it. To some this highlighted a few points, that there is a reason RHELexists with full paid support, and also that this could be a vulnerability and huge flaw with yum. A yum search or install should not segfault just because the rpmforge repo goes down. Fortunately it came back up........

Linux Out of Memory OOM Object Killer Solution "Out of memory: kill process 1955 (sshd) score 81 or a child"

I had a system running a 128MB live CD image with 2.8 gigs of available RAM and the OOM kernel killer went crazy when using dd for more than 8 minutes and kept killing everything. I've read that this is due to a low-memory issue and paging in the kernel and 32-bit systems with lots of RAM. I even enabled swapspace on my LiveCD and the issue happened 25 minutes into dd rather than 8 minutes, so what gives? Also no swap space was ever used! cat /proc/s........

Kernel/make compilation time and how to improve compile times/compile the Linux kernel faster without hardware upgrades

I thought only a faster CPUand SSDwould help but I already have a Quad-Core CPU and it wasn't being maxed out. The actual tests were performed on an AMD-V enabled 128MB dual core VMWare container though. There is a flag that can be passed to make in order to start multiple threads, by specifying 4 threads I was able to reduce the whole kernel compilation time from scratch by about 50%! (65minutes vs 31minutes!). *Yes I did do a make clean before each co........

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........

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

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........

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. ThenI 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........

Openvz Disk quota exceeded inode problem with free space

Openvz problem, it is confusing because it's an inode issue and there is enough free space. cp: cannot create regular file `forums/memberlist.php': Disk quota exceeded /dev/simfs 60G 20G 41G 33% / none 2.0G 4.0K 2.0G 1% /dev........

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........

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........

Ubuntu 10.04/GRUB2 mdadm won't boot

Moving to RAID was a pain. What you have to do is the following from an existing install: Install mdadm Create your mdadm RAID 1 array on your spare hard drive. Start it with the missing disk. rsync the entire contents of your current / to the md partition. Here's a good way of doing it: rsync -Pha --exclude=/proc/* --exclude=/sys/* --exclude=/mnt/* /. /mnt/md2........

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........

http://apt.sw.be/redhat/el5/en/i386/test/repodata/repomd.xml: [Errno 14] HTTP Error 404: Not Found Trying other mirror.

http://apt.sw.be/redhat/el5/en/i386/test/repodata/repomd.xml: [Errno 14] HTTP Error 404: Not Found Trying other mirror. Error: Cannot retrieve repository metadata (repomd.xml) for repository: rpmforge-testing. Please verify its path and try again Notice it is complaining about "rpmforge-testing", just disable it for now: Solution is to edit the repo: vi /etc/yum.repos.d/rpmforge-testing.repo........

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........

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 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........

How To Enable 3rd/third party packages in RHEL/Redhat/Centos 4/5 Linux via RPMForge

It's a bit of a pain that many basic third party tools that aren't put of the main Centos/RHEL repositories are not available unless you compile them or install the RPMForge Repo. *Updated 08/29 with new download location changed from apt.sw.be to rpmforge.sw.be Here's a quick, simple/cut&paste way to do it: wget http://rpmforge.sw.be/redhat/el5/en/i386/rpmforge/RPMS/rpmforge-release-0.5.1-1.el5.rf.i386.rpm rpm -i rpmforge........

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........

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 HNitself 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. Ichecked my /proc/user_beancounters and found this: cat /proc/user_beancounters Version: 2.5 uid resource held maxheld barrier limit failcnt........

OCFS2 crash

When trying to even cd or ls the mounted OCFS2 partition it crashes. Ithink this is a combination of VMWare Server's problem and the way I mounted and symlinked to it. More than anything this shows the problem and lack of forsight with VMWare, but also that OCFS2 is easily crashed if you do strange things. Output of /var/log/messages for OCFS2 Apr 10 15:57:45 localhost kernel: [84331.691258] Modules linked in: vmnet vmci vmmon ocfs2_stac........

Configuring OCFS2 Clustered File System on Debian Based Linux including Ubuntu and Kubuntu

There's a lot of information and guides on OCFS2 for RHELand Centos Linux but the package setup and configuration is slightly different and this has thrown some people off. Installing OC2FS You should install the following packages to get started: apt-get install ocfs2-tools ocfs2console Configure OC2FS In RHEL/Centos the main configuration file is located in /etc/sysconfig/o2cb However in Debian based Linux it is located........