• Cisco CME and C7200 Router Testing and Learning Environment on Ubuntu 20+ Setup Tutorial Guide


    Since newer versions of Ubuntu like 20, you will find there is no longer dynagen and that the dynamips provided is faulty and will segfault each time: Cisco Router Simulation Platform (version 0.2.14-amd64/Linux stable) Copyright (c) 2005-2011 Christophe Fillot. Build date: Apr 3 2018 12:20:29 Local UUID: 3c1c0b7f-2fab-4fda-b40b-74841d1bcfe0 Instance ID set to 1. netio_tap_create: unable to open TAP device tap1 (No such fi........

  • How to Install Any OS on a Physical Drive from Windows Using VMware Workstation (Linux, Windows, BSD)


    Uses: Install OS on physical drive Linux installation VMware Install Windows on physical drive Boot OS from physical drive VMware Workstation tutorial Linux virtual machine to physical disk Windows to Linux migration Dual boot OS installation Boot from external SSD Linux, Windows, BSD installation guide Physical drive boot OS........

  • Dell Server Workstation iDRAC Dead after Firmware Update Solution R720, R320, R730


    This is certainly a poor design, as you can read many seasoned admins who have updated their iDRAC only to have it killed. One possible cause is not by doing all the incremental updates, doing updates from an old iDRAC to one many revisions newer is a sure way to kill things, but even then there is no guarantee based on the amount of failures. List of threads of people's dead iDRAC's:........

  • Cloned VM/Server/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........

  • Linux Debian Mint Ubuntu Bridge br0 gets random IP


    This can break things easily in remove environments where it was normally easy to convert a normal eth0 to a bridge under br0, and that bridge would normally have the same MAC address by default, which is desirable for most situations. In Debian 11 this is different for some reason now. https://unix.stackexchange.com/questions/681013/bridge-gets-random-mac-........

  • redis requirements


    sysctl vm.overcommit_memory=1 echo never > /sys/kernel/mm/transparent_hugepage/enabled echo 511 > /proc/sys/net/core/somaxconn 1:M 26 Nov 2023 21:34:33.840 # WARNING: The TCP backlog setting of 511 cannot be enforced because /proc/sys/net/core/somaxconn is set to the lower value of 128. 1:M 26 Nov 2023 21:34:33.840 # Server initialized 1:M 26 Nov 2023 21:34:33.840 # WARNING overcommit_memory is set to 0! Background sa........

  • 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........

  • docker swarm silly issues


    The error below can be caused by a gateway that is unpingable: docker swarm join --token SWMTKN-1-1kogg8da68gtb1j7ezaddowyy9s0an5s9tue758o20k18liskw-5h3f61hrrmv3u6agshvbtcklf 172.16.1.80:2377 Error response from daemon: manager stopped: can't initialize raft node: rpc error: code = Unknown desc = could not connect to prospective new cluster member using its advertised address: rpc error: code = DeadlineExceeded desc = context deadline exceeded........

  • isc-dhcp-server dhcpd how to get longer lease


    You can do a static lease that is tied to the MAC address but what a lot of users prefer is that they come into the office or lab the next day and that their device gets assigned the same IP address (if possible). As we can see in the dhcpd logs that there is threshold that is defaulted as we'll show later. Whatever the threshold is set at, if the lease is younger than the threshold, it will keep the same lease. In other words, if the device goes to sleep or is powered off........

  • docker error not supported as upperdir failed to start daemon: error initializing graphdriver: driver not supported


    Nov 15 17:00:49 rttbox kernel: overlayfs: filesystem on '/var/lib/docker/overlay2/check-overlayfs-support450709549/upper' not supported as upperdir Nov 15 17:00:49 rttbox dockerd[93755]: failed to start daemon: error initializing graphdriver: driver not supported The above error is often/normally caused because you are trying to run docker out of an unsuitable directory/filesystem. For example if you try to place docker's data inside an existing overl........

  • qemu-system-x86_64: Initialization of device ide-hd failed: Failed to get


    You start a qemu like this and another VM already started with the same .iso qemu-system-x86_64 -enable-kvm -m 4096 -cdrom some.iso But you get this error: qemu-system-x86_64: Initialization of device ide-hd failed: Failed to get "write" lock Is another process using the image [some.iso]? It's odd because the -cdrom by default is read-only and qemu should not want or care about getting write lock on........

  • File "/usr/local/lib/python3.5/dist-packages/pip/_internal/utils/entrypoints.py", line 12 f"pip{sys.version_info.major}", ^ SyntaxError: invalid syntax python pip3 error solution


    Is python3-pip pip3 not working anymore? Traceback (most recent call last): File "/usr/bin/pip3", line 11, in sys.exit(main()) File "/usr/local/lib/python3.5/dist-packages/pip/__init__.py", line 11, in main from pip._internal.utils.entrypoints import _wrapper File "/usr/local/lib/python3.5/dist-packages/pip/_interna........

  • Docker Swarm vs Kubernetes Comparison Guide


    A lot of companies are unsure which solution to choose and many may not be aware of Docker Swarm as an alternative to Kubernetes. One thing that many Sysadmins find is that Docker Swarm is simply easier, quicker to setup and maintain by far than Kubernetes.........

  • Install Grafana on Linux Debian Ubuntu Tutorial Guide


    First we need a few extra packages: apt update apt install -y adduser libfontconfig1 musl sudo wget https://dl.grafana.com/enterprise/release/grafana-enterprise_10.3.1_amd64.deb Install / Enable Grafana dpkg -i grafana-enterprise_10.3.1_amd64.deb dpkg -i grafana-enterprise_10.3.1_amd64.deb (Reading database ... 44309 files and directories currently installed.) Preparin........

  • System has not been booted with systemd as init system (PID 1). Can't operate. Failed to talk to init daemon. Ubuntu Debian Linux Solution Cannot reboot


    You are probably using some custom image or maybe this is some sort of container that didn't boot with systemd. The solution is to use "reboot -f" reboot -f This will force the system/OS/VM/container to reboot.........

  • 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://........

  • Docker dockerd swarm high CPU usage cause solution


    If you have swarm services and dockerd is creating a high load even with the containers just being idle, the easiest solution is to upgrade to a newer docker version. For example an identical config of 3 nodes, with Redis 5 with 30 replicas produces a load of about 1.45 in Debian 10 with Docker18.09.1 If I create the same setup on Debian 11, with Docker 20.10.5+dfsg1 then the CPU usage is low. One other difference I wondered is the kernel. In my test setup........

  • request_module: runaway loop modprobe binfmt-464c Kernel panic - not syncing: No init found Pid: 1, comm: swapper/0 Not tainted solution


    request_module: runaway loop modprobe binfmt-464c Kernel panic - not syncing: No init found Pid: 1, comm: swapper/0 Not tainted This is usually caused by a mismatch in architecture and happens frequently in development environments. Here is a example of what caused this issue: Your binaries are based on one architecture Your kernel was compiled with another architecture. Why does this happe........

  • How to upgrade to the latest Python version on Linux Ubuntu Debian Mint 3.11


    A lot of developers want to go to 3.11 because of the speed improvements, but most distros never have the latest Python version. Using the deadsnakes third party repo is the easiest way aside from compiling it yourself (which is safer and recommended): Step 1 - Add the repo apt-add-repository ppa:deadsnakes/ppa If you get an error about requests then install it:........

  • 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........

  • python3 error Ubuntu Linux error solution SyntaxError: invalid syntax line 12 pip{sys.version_info.major}


    This sort of thing normally happens your python3 or pip3 has been updated, because you have to in order to use pip, but the newer pip now breaks compatibility with your old python (3.5 in this case). There are a few solutions, the easiest is perhaps to upgrade to a newer OS with a newer distro provided Python 3 or to manually install a newer version of Python/OR use a PPA like deadsnakes that provides newer versions. ........

  • How to install and configure haproxy on Linux Ubuntu Debian


    haproxy is one of the best known and widely used Open Source load balancers out there and a strong competitor to nginx. haproxy is used by many large sites per Wikipedia: HAProxy is used by a number of high-profile websites including GoDaddy, GitHub,........

  • talib/_ta_lib.c:747:10: fatal error: ta-lib/ta_defs.h: No such file or directory


    If you are installing ta-lib for Python and get this error then you can normally solve it by manually getting the ta-lib source files and compiling. tar -zxvf ta-lib-0.4.0-src.tar.gz cd ta-lib;./configure;make;make install Collecting ta-lib Downloading https://files.pythonhosted.org/packages/39/6f/6acaee2eac6afb2cc6a2adcb294080577f9983fbd2726395b9047c4e13ec/TA-Lib-0.4.26.tar.gz (272kB) &nbs........

  • How to install Windows or other OS and then bring to another computer by using a physical drive and Virtual Machine with QEMU


    This has been a tried and true method for Windows because it is finicky with hardware changes without a reinstall (eg BSOD on boot is what happens 9/10 times unless you move to the same hardwar). Surprisingly, if you use a QEMU VM and do a standard install, it has worked in every system I've thrown the drive in afterwards. So the play is this, use a USB SSD, physical SATA drive plugged internally or for convenience, you could use a SATA to USB adapter on another computer to perf........

  • vagrant install on Debian Mint Ubuntu Linux RHEL Quick Setup Guide Tutorial


    1 - Install Vagrant apt install vagrant Make sure you have a supported Virtualization tool like Virtualbox or VMWare, Hyper-V etc.. It automatically detects and uses what you have. Virtualbox has a lot of support here with tons of images. 2 - Init Vagrant We'll init to have a Debian 10 box by default to show how quick and easy it is. vagrant init generic/debian10........

  • 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........

  • debootstrap how to install Ubuntu, Mint, Debian install


    In this example we install debian 10 with --variant=minbase which gives us a minimal/tiny install. Don't use variant if you want the full size install. mkdir /tmp/deb10files debootstrap --variant=minbase buster /tmp/deb10files/ Did you get an error? debootstrap --variant=minbase buster /home/theuser/VMs/deb10files/ You'll get this error if you make a directory in your home........

  • 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........

  • grub blank screen how to manually boot kernel and initrd Linux Ubuntu Debian Centos won't boot solution


    You probably didn't do an "update-grub" and grub no longer has any proper menu entries, but before you can fix it let's try to get grub booting anyway. If you get this lovely black grub screen here's how you can get things booting. In my case I have a gpt partition with partition 1 and 2. Partion 1 is just my EFI / ESPand partion 2 /dev/sda2 is my root which includes /boot. You will have to adjust this if you had a separate /boot partition.........

  • Cisco Switch / Router How To Restore Factory Default Settings


    1.) Make sure your conf register is 0x2102 Do show version and at the very end of the output you will see the Configuration register. show version Configuration register is 0x2102 If the config register is not 0x2102 then enter this command: r1#configure terminal r1(config)#config-register 0x2102 r1(config)#end 2.) Let's Erase the NVRAM/flash........

  • Cisco 2900 3900 Router Password Reset How To Reset Enable Password


    It is a bit different and annoying here for these types of routers/models as you need to physically remove the CF (Compact Flash) and only then, will it enter ROMMON mode (Ctrl + Pause remotely over the console will not do it for us). This means you cannot do this remotely, or at least not without the help of a remote/physical helper. Step 1.) Power off, router and remove CF Disk Slot#2 Go to the router and remove the slot#2 cover uses your hand or it may help to use a........

  • 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........

  • Loaded: masked (Reason: Unit hostapd.service is masked.) Solution in Linux Debian Mint Ubuntu


    If you are getting this error from systemctl "Loaded: masked (Reason: Unit hostapd.service is masked.)" we need to unmask the service. Solution systemctl unmask hostapd Removed /etc/systemd/system/hostapd.service. It's fixed root@routerOS:/var/log# systemctl start hostapd root@routerOS:/var/log# systemctl status hostapd ● hostapd.service - Access point and authentication server for Wi-Fi and Ethern........

  • 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........

  • amdgpu AMD GPU Xorg Won't Start [3576284.324] (EE) Segmentation fault at address 0x0 [3576284.325] (EE) Fatal server error: [3576284.325] (EE) Caught signal 11 (Segmentation fault). Server aborting


    Here is how Ifixed it on a Mint/Ubuntu install 1.) First download the latest AMDGPU-Pro driver from here: https://www.amd.com/en/support Navigate to your relevant video card: 2.) Download the installer One issue is that by default they give you a version for the latest version of........

  • LightDM Mint Ubuntu Debian won't start errors Nvidia Graphics


    This error implies that there may be an issue with Xorg or maybe your NVIDIA GPU cannot start or initialize: 35 laptop kernel: [ 2031.857704] nvidia: loading out-of-tree module taints kernel. 35 laptop kernel: [ 2031.857724] nvidia: module license 'NVIDIA' taints kernel. 35 laptop kernel: [ 2031.857725] Disabling lock debugging due to kernel taint 35 laptop kernel: [ 2031.873280] nvidia: module verification failed: signature a........

  • How To Do Linux Network Bonding Teaming in Mint Debian Ubuntu


    Bonding is an excellent way to get both increased redundancy and throughput. It is similar to the "Network Teaming" feature in Windows. There are a few different modes but we will use mode 6, I think it's the best of both worlds, as it is not just a failover, but it provides round robin, so you will get redundancy and load balancing. So if you have a 1G single port, you will have a combined throughput of 4G at this point. Just bear in mind that the true thr........

  • LXC Containers LXD How to Install and Configure Tutorial Ubuntu Debian Mint


    If you are using mint, delete the preference that stops snap from installing (as it is required for lxc) sudo rm /etc/apt/preferences.d/nosnap.pref 1. Install lxd: sudo apt install lxd Issues install lxd or errors? Click here Debian at this time does not have lxd so you'll need to use snap: sudo apt in........

  • Docker Tutorial HowTo Install Docker, Use and Create Docker Container Images Clustering Swarm Mode Monitoring Service Hosting Provider


    The Best Docker Tutorial for Beginners We quickly explain the basic Docker concepts and show you how to do the most common tasks from starting your first container, to making custom images, a Docker Swarm Cluster Tutorial, docker compose and Docker buildfiles.........

  • Zoom Password Error 'That passcode was incorrect' - Solution Wrong Passcode Wrong Meeting Name


    Have you been given a Zoom password that the meeting owner says is correct but it doesn't work anymore or never works? If the meeting name says "Zoom Meeting" and it's not really named that (which most meetings are not), then the issue is usually that there is an initial password to be able to join, aside from the passcode. It basically means that Zoom has deauthenticated you randomly or maybe after X amount of uses, without clicking on the Join Meeting URL which contains a........

  • How To Create OpenVPN Server for Secure Remote Corporate Access in Linux Debian/Mint/Ubuntu with client public key authentication


    Why choose OpenVPN instead of a firewall appliance? OpenVPN can be a reliable and easy replacement for traditional hardware or just be an additional tool that your company uses so that the firewall can focus on its job rather than acting as a VPNappliance at the same time. When comparing OpenVPN with traditional firewal........

  • 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........

  • pulseaudio issue on QEMU/KVM guest VM when microphone is replugged/unplugged pulseaudio: pa_threaded_mainloop_lock failed pulseaudio: Reason: Invalid argument


    Here is the scenario, you are using QEMU/KVM and are using something like the AC97 sound driver to pass the host audio to the guest via pulseaudio. This is useful because you can transparently pass your mic input from the host which means you can mute your microphone from the host, which prevents the guest from receiving any mic input even if unmuted. Mute / Unmute Fix This issue also seems to happen even if you press the mute button on the microphone and then unmute,........

  • 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........

  • Cisco Switch Howto Reset Password


    This was done on a 2900 but applies to all the switches of the same era. Step 1 - Power Cycle and enter recovery mode If you have physical access you can power cycle and hold the mode button down for 15 seconds. After that the SYS light will flash on the switch and you will see the following screenshot. If you don't have physical access (eg. it is a datacenter swich over console only) then power cycle and hit "Ctrl+Pause/B........

  • Cisco Router Password Reset Howto Guide Solution Cannot Login /Unknown Enable Password 2600, 2800, 2900, 3900


    It is common that you may get access to undocumented equipment and need to reset the password. This applies to many Cisco routers whether 2600, 2900, 3900 etc... Cisco's Guide says to hit Ctrl +Pause/Break but if it doesn't work on some devices causing people to say "cisco password reset pause break does not work", you can see Cisco's alternative key combinations here:........

  • 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........

  • Juniper JunOS Command Overview and Howtos Switch, Router, Firewall Tutorial Guide


    Enable "cli" mode equivalent in JunOS cli Configure Mode configure So rather than going to the console on a Cisco switch and typing "enable" and then "conf t", the equivalent in JunOS is "cli" and "configure". How Do You Apply Changes You've Made? You can make all kinds of changes to the switch, but remember they are not........

  • 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.........

  • CentOS 6 impossible to compile a newer libguestfs


    yum -y install gcc make gperf genisoimage flex bison ncurses ncurses-devel pcre-devel augeas-devel augeas readline-devel checking for cpio... cpio checking for gperf... no configure: error: gperf must be installed configure: error: Package requirements (augeas >= 1.2.0) were not met: Requested 'augeas >= 1.2.0' but version of augeas is 1.0.0 yum remove augeas augeas-libs augeas-devel wget http://downl........

  • How To Get Started on Ubuntu with gpt-2 OpenAI Text Prediction


    apt install software-properties-common add-apt-repository ppa:deadsnakes/ppa apt update apt install python3-pip apt install python3.7 curl gnupg python3.7-dev git ln -s /usr/bin/python3.7 /usr/bin/python3 pip3 install numpy keras_preprocessing curl https://bazel.build/bazel-release.pub.gpg | sudo apt-key add - echo "deb [arch=amd64] http://storage.googleapis.com/bazel-apt stable jdk1.8" | sudo tee /etc/apt/sources.list.d/bazel........

  • Remove cloud-init in your VM


    Unless you are using OpenStack, AWS etc then cloud-init is just some bloat that slows down the booting of your VMand can actually halt it from booting if it doesn't have a proper working IP (not good!). #remove cloud init! Debian based Ubuntu / Mint sudo apt remove cloud-init RHEL / CentOS based yum remove cloud-init ........

  • 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........

  • 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.)........

  • Debian and Netplan


    Create your netplan file vi /etc/netplan/01-netcfg.yaml network: version: 2 renderer: networkd ethernets: ens3: dhcp4: no ........

  • 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........

  • how to use ifplugd in Linux to execute a command or script when a NIC cable is unplugged or plugged in


    It is fairly simple to use once you know how to use it. However, the tricky thing is that by default it doesn't seem to be active or listen on any interface on manually specified. How To Install ifplugd First we install ifplugd sudo apt install ifplugd Let's enable it on our desired device(s) vi /etc/default/ifplugd set this line as so:........

  • mpv / mplayer with Radeon / AMD GPU Video Card Driver enable VDPAU GPU Accelerated Video Decoding


    The easiest way to know if your videos are playing with GPU acceleration are to watch the process of xplayer, mpv or whatever you are playing. The CPU usage should be no more than 10% for that process/program if it is using acceleration. Let's manually play with vdpau to make sure it works before we make it permanent: First make sure you have libvdpau installed: sudo apt install vdpau-driver-all If yo........

  • 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........

  • CentOS 6 and 7 / RHEL Persistent DHCP Solution


    It is very silly but the default on the ifup-eth script tells dhclient ( the program that obtains a DHCP IPaddress if you have selected DHCPin your ifcfg-eth* config file) to EXIT / QUIT if the first attempt to obtain a lease fails. No amount of dhclient.conf settings will fix this because if dhclient is started with -1 (which it is by default)then dhclient will quit. This is obviously very bad for MOST cases. Say for example you have a power outage or........

  • python import docx error


    sudo pip3 install python-docx [sudo] password for : Downloading/unpacking python-docx Downloading python-docx-0.8.10.tar.gz (5.5MB): 5.5MB downloaded Running setup.py (path:/tmp/pip_build_root/python-docx/setup.py) egg_info for package python-docx no previously-included directories found matching 'docs/.build' warning: no previously-included files matching '.DS_Store' foun........

  • qemu-kvm error "Could not initialize SDL(No available video device) - exiting"


    Now older versions of qemu-kvm didn't throw this error say if you just had "-video cirrus" when starting qemu-kvm. But newer versions do care. And this probably only applies to you if you are running from bash/terminal with remote kvm images. What you need to do is remove the "-video" part and just add -vnc :5 eg. this would fix the error: qemu-system-x86_64 -enable-kvm -boot order=cd,once=dc -m 1024 -drive........

  • 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........

  • Virtualbox vbox not starting


    If you've just installed VBox and it is not starting or working, the most common problem is usually that you don't have your kernel source installed, which means there is no kernel driver for vbox so it can't work. You may get an error that says "Kernel driver not installed" in your Virtualbox. So the first thing you should do is install your kernel source by running this: sudo apt-get install linux-headers-`uname -r`........

  • Ubuntu/Gnome/Mint/Centos How To Take a partial screenshot


    By default printscreen or alt print screen will get the whole desktop or the application in focus, respectively. But what if you want to select a portion of the screen? gnome-screenshot: ksnapshot compiz This is a nicely integrated solution sudo apt-get install compizconfig-s........

  • Cisco Unified Communications Manager / CUCM IP 8.6,10,12 Install Error Solution


    Install Errors on Version 12: This error happened on QEMU emulator version 2.11.1 pve-qemu-kvm_2.11.1-5 on Proxmox/Debian but installing on QEMU.12 on Centos 6 did not produce the error. *Update it is not related to the OS or QEMU version. This happened in Centos 6 too after a second install. What really causes this even though you successfully install........

  • Cisco Unified Communications Manager 12 Install Errors on Proxmox/KVM


    The strange thing is that usually the first install or two will work on any new machine but then it suddenly won't. I had this experience on QEMU 2.13 on a different machine. There is something finicky or buggy about the CUCM installer even when choosing the same virtual hardware specs. qemu-kvm command: /usr/libexec/qemu-kvm -version QEMU PC emulator version 0.12.1 (qemu-kvm-0.12.1.2-2.506.el6_10.1), Copyright (c) 2003-2008 Fabrice Bellard ........

  • Cisco Unified Communications Manager / CUCM IP Telephony Definitions


    DN = Directory Number: It is basically the extension of the phone In the example below, 55 is a DN assigned to the phone.........

  • Linux bash prompt why does it not show username@host and the current directory?


    Perhaps you've just seen this in the bash prompt: -bash-4.1# Instead of the expected user@hostname# It is probably because you are missing .bash_profile or .bashrc in your home directory Check for yourself: ls -al ~/|grep -E ".bash_profile|.bashrc" -rw-r--r--. 1 root root&nbs........

  • Cisco Switch Reset To Factory Defaults


    This works on the 2000 and 3000 series generally. *The easy way is to just hold the mode button for 10+ seconds. The full/proper way is below: 1.) Either power on the unit and hold the "mode" button or hold the "mode" button until you see the below: 00:04:08: %SYS-7-NV_BLOCK_INIT: Initalized the geometry of nvram 00:04:08: %EXPRESS_SETUP-6-CONFIG_IS_RESET: The configur........

  • Debian Linux Mint Ubuntu iptables save and restore settings automatically onboot and reboot


    First you need the "iptables-persistent" package. This gives you an init script that loads your settings from /etc/iptables/rules.v4 and rules.v6 When you install it, it wll save your default setings in /etc/iptables. sudo apt-get install iptables-persistent Remember that the rules are stored here: For IPV4: /etc/iptables/rules.v4 For IPV6: /etc/iptables/r........

  • VirtualBox How To Add iSCSI Storage using VBoxManage


    #to show all VBoxManage list vms #show ONLY running vms VBoxManage list runningvms VBoxManage storageattach test --storagectl "SATA" --port 0 --device 0 --type hdd --medium iscsi --server 192.168.1.91 --target "iqn.2018-12.local.abcrandom.target:sdb" --initiator "iqn.1982-01.ca.bla.tld:abc123" --t........

  • iSCSI on Centos 7 Configuration and Setup Guide for Initiator and Target


    initiator = client target = server These are the first concepts you should understand which is that in iscsi essentially the "initiator" is the client and the "target" is the server. iSCSI is derived from the old fashioned SCSI that us oldtimers grew to love. The "i" stands for Internet and the SCSI stands for "Small Computers Systems Interface" (SCSI). iSCSI Target (Server)Setup targetcli is the pac........

  • How Does Cisco CUCM (Cisco Unified Communication Manager) Work?


    Cisco's CUCM (Cisco Unified Communication Manager) is a system that combines voice, video, data and mobile products into a single unified management suite. At its core, the CUCMis like a "Super PBX" that controls the flow of all communications through an organization even single or multiple site deployments. Cisco's CUCMmakes communication more effective and simple through centralized management and unification of communications resources.........

  • 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........

  • Linux bash shell doesn't show username, hostname or current path fix solution


    Usually this is because when you created your user you added a user but didn't create their home directory and/or for some reason your .bashrc and .bash_profile in ~ (home) is broken/missing. In your home just create the following files with the following content to solve it: .bashrc and .bash_profile. To apply it just relogin/start a new bash session # .bash_profile # Get the aliases and funct........

  • 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........

  • Install NFS (Network File System) On Debian Linux Ubuntu Mint Howto


    sudo apt-get install nfs-kernel-server #oops there are no exports so it won't startsudo /etc/init.d/nfs-kernel-server start* Not starting NFS kernel daemon: no exports. #we will use the /tmp/nfstestshare directory for our NFS share mkdir /tmp/nfstestshare #add it to /etc/exports (basically what NFS checks to determine what to make an NFS share) /tmp/nfstestshare 192.168.1.5(rw,sync,........

  • 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........

  • Cannot create gradle for conversations


    The main issue is it looks like Java is not configured to accept the invalid ssl cert that is coming from the download location. Exception in thread "main" java.lang.RuntimeException: javax.net.ssl.SSLException: java.security.ProviderException: java.security.InvalidKeyException: EC parameters error export ANDROID_HOME=/home/user/Downloads/tools/ Conversations-master$ ./gradlew Downloading https://services.gradle.org/distributions/grad........

  • OpenVPN cannot ping remote IP routing loop issue after connecting


    Sometimes if you have a very basic configuration OpenVPN on the client side for some reason sends all traffic to the OpenVPN server IP through the tun0 which is of course impossible and creates a block or routing loop. This is because you need to use your normal ISP/LANgateway to hit the OpenVPN server if it is remote/offsite as is usually the case. So if you are connected to the OpenVPN through say a tun0 device and your routing is set to connect to the OpenVPN&nbs........

  • 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........

  • Centos PXEBoot NetInstall Failure - Pane is dead


    ValueError: new value non-existent xfs filesystem is not valid as a default fs type Pane is dead From what Iread this is misleading and has to do with the fact that the initrd and kernel are mismatched. This is a hard situation because for some older hardware Iam using the Centos Plus kernel which has modules that Irequire for an older server/NIC. This seems to have cropped up in the past few months and there is no simple fix........

  • Linux Ubuntu Mint Debian cannot play xvid,x264,mp4 or any videos codec issue - xplayer Could not initialize supporting library.


    In xplayer Iget the following error "Could not initialize supporting library.". It actually looks more like a gstreamer issue. For those wondering what the default video player is called it is "xvid" and not "totem" anymore like previous versions. Basically it looks like some codecs are missing when I uninstalled another program it uninstalled other programs and codecs that it shouldn't have. I've tried installing all the gstre........

  • 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........

  • How To Install Windows Server 7 8 10 12 2008 2012 2014 2016 Servers Desktops using Linux tftp, dhcpd and samba


    It has been a big pain for a long-time to install Windows from a Linux environment. I used to run a windows install server and it never worked right for some reason (the install would fail on most servers). Before getting start be sure to setup your samba share so once you boot into WinPE you can mount the install for whatever Windows you want /etc/samba/smb.conf [smbwinstall] path = /tftpboot/images/winstall guest ok = yes........

  • OpenVZ Solutions vzquota : (error) Can't open quota file for id 123123, maybe you need to reinitialize quota: No such file or directory


    Error: Unable to apply new quota values: quota not running Container start failed (try to check kernel messages, e.g. "dmesg | tail") Killing container ... Container was stopped Error: Unable to apply new quota values: quota not running Can't umount /vz/private/123123: Invalid argument [root@rtt 123123]# vzquota on 123123 vzquota : (error) Can't open quota file for id 123123, maybe you need to reinit........

  • Debian Mint Ubuntu Linux Server Password Forgotten Reset Password Solution Centos 7 8 Root Password Reset Recovery


    This guide will work for most modern Linux versions like Centos RHEL 7, Debian, Mint, Ubuntu etc... In Centos 7 the days of editing the "kernel"line and adding "single"are gone. On top of that sometimes after a new install passwords do not work, maybe you forgot your password or for some other reason you need to break in or fix your system? It could also be because you can't mount your root / or some other /etc/fstab error and many other err........

  • Install Windows From a Linux TFTP Server instead of using WDS Solution


    yum -y install samba vi /etc/samba/smb.conf https://www.kernel.org/pub/linux/utils/boot/syslinux/syslinux-6.03.zip mkdir syslinux;cd syslinux;unzip syslinux-6.03.zip mkdir -p /tftpboot/libs/ cp bios/com32/modules/linux.c32 /tftpboot/libs/ cp bios/com32/libutil/libutil.c32 /tftpboot/libs/ cp bios/com32/lib/libcom32.c32 /tftpboot/libs/ #add lib path echo "PATH libs" >> /tftpboot/pxeli........

  • pcimodules and lspci not working alternative solution


    pcimodules no longer works it produces nothing probably because the format of /sys/bus/pci is different. lspci -k doesn't work on older lspci versions. pciutils can be compiled but it won't work if you have an old system and compile on a newer glibc. iteriate through /sys/bus/pci/devices/*/modalias cat /sys/bus/pci/devices/*/modalias pci:v00008086d00001237sv00000000sd00000000bc06sc00i00 pci:v00008086d00007000sv0000000........

  • 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........

  • [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........

  • linux cp and mv will not overwrite due to alias!


    This through me for a loop when I would do a cp -rf or mv -f nothing would get overwritten even if piping y or yes to the command. Type alias and you'll see why: alias cp='cp -i' alias l.='ls -d .* --color=auto' alias ll='ls -l --color=auto' alias ls='ls --color=auto' alias mv='mv -i' alias rm='rm -i' The -i is a safeguard against messing things up but however does mess things up worse when you know what........

  • iptables v1.4.7: can't initialize iptables table `NAT': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded.


    iptables -t NAT -A PREROUTING -s 24.30.44.0/24 -j DNAT --to-destination 10.10.10.1 iptables v1.4.7: can't initialize iptables table `NAT': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. Solution # it is case sensitive "nat" and DO NOT use "NAT" or you will get this error! iptables -t nat -A PREROUTING -s 24.30.44.0/24 -j DNAT --to-destination 10.10.10.1........

  • 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........

  • kdenlive titles/text renders as white screen when using .sh script


    When using the .sh script the rendering doesn't work after an upgrade of related packages to kdenlive. kdenlive (kdenlive:amd64 (4:17.04.1+git201705191233~ubuntu16.04.1)) with affine or composite transitions was fine but is now broken during the time of transition it is just a white screen. The previous version was fine: kdenlive:amd64 (4:17.04.1+git201705191233~ubuntu16.04.1 But now I can't find it or install it:........

  • [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 trouble concatenating similar but different files


    When things go wrong your video is basically unplayable or the first video plays fine and then freezes when moving on to the next. Generally if both videos weren't produced with the exact 100% same settings you will have issues. You can try the basic concat but it often won't work right. Solution for me: My example uses 3 videos in total so "n=3" and a=1 to include audio. ffmpeg -threads 12 -i file1.mp4 -........

  • ffmpeg Unable to Use Hardware Encoding with Nvidia 3.40 Driver and GT210 card


    I believe from what I've read that this card's driver doesn't support the features after trying all known troubleshooting methods. ffmpeg -i uservideoRendered.mp4 -filter:v hwupload_cuda,scale_npp=w=1920:h=1080:format=nv12:interp_algo=lanczos,hwdownload -c:v hevc_nvenc -profile main -preset slow -rc vbr_hq -c:a copy uservideoRendered.mp4-test ffmpeg -i uservideoRendered.mp4 -filter:v hwupload_cuda,scale_npp=w=1920:h=1080:format=nv12:interp_algo=lanczos,hwdownload........

  • 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........

  • How to change reserved blocks in Linux partition


    user@box:~$ sudo tune2fs -l /dev/md99 [sudo] password for user: tune2fs 1.42.9 (4-Feb-2014) Filesystem volume name: Last mounted on: /mnt/md50 Filesystem UUID: 976a8655-2619-4587-878c-dab07f7b7652 Filesystem magic number: 0xEF53 Filesystem revision #: 1 (dynamic) Fi........

  • 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........

  • 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........

  • 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"........

  • Linux how to whois query other gTLDs such as .club solution


    whois in Linux is incredibly out of date and does not seem to recognize most new TLDs domains, but there is a quick and easy tip/hack/tweak for this. An example of new TLD's site as .review .site .club whois somesite.club No whois server is known for this kind of object. bash to the rescue Now I did try to apply this in .bashrc but DONOT! Ithink the * wil........

  • 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 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........

  • DRBD Split-brain solution


    Uh oh [17925926.174277] block drbd0: Handshake successful: Agreed network protocol version 96 [17925926.174325] block drbd0: conn( WFConnection -> WFReportParams ) [17925926.174342] block drbd0: Starting asender thread (from drbd0_receiver [1682]) [17925926.174432] block drbd0: data-integrity-alg: [17925926.174581] block drbd0: drbd_sync_handshake: [17925926.174586] block drbd0: self 2AAE66AF9252D6DB:2815BF........

  • ERROR 2013 (HY000): Lost connection to MySQL server during query


    The solution is simple but strange, if you copy your /var/lib/mysql directory to another server and think it will work, be sure to check if you have /var/log/mysql and binary log files. If you do, the server will not work and will give you errors like below and crash without the proper log files. UPDATE user SET password=password("newpass") WHERE user='root'; flush privileges; ERROR 2013 (HY000): Lost connection to MySQL server durin........

  • MySQLD Server shutdown remotely unexpectedly


    170110 5:35:23 [Note] /usr/libexec/mysqld: Normal shutdown 170110 5:35:23 [Note] Event Scheduler: Purging the queue. 0 events 170110 5:35:23 InnoDB: Starting shutdown... 170110 5:35:24 InnoDB: Shutdown completed; log sequence number 0 12765401 170110 5:35:24 [Note] /usr/libexec/mysqld: Shutdown complete 170110 05:35:24 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended........

  • mcp55 NIC not working at boot on Centos 6.6-6.8


    forcedeth 0000:00:08.0: irq 25 for MSI/MSI-X forcedeth 0000:00:08.0: eth0: MSI enabled forcedeth 0000:00:08.0: eth0: no link during initialization ADDRCONF(NETDEV_UP): eth0: link is not ready forcedeth 0000:00:08.0: eth0: link up ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready Dec 1 18:21:32 box15 kernel: forcedeth: Reverse Engineered nForce ethernet driver. Version 0.64. Dec 1 18:21:32 box15 kernel........

  • 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........

  • Ubuntu/Debian OpenVZ Template Problems No Networking and SSH not starting


    It all comes down to a bug essentially where you are running an older kernel that doesn't support the newer Debian templates. The solution is to update your OpenVZ kernel. Here are some symptoms of the problem/lack of kernel support: Ubuntu Template 12.04 requires a manual network start: service networking start sshd will not start: /usr/sbin/sshd PRNG is not seeded mknod /dev/random c 1 8........

  • Centos and obfsproxy install errors


    pip install obfsproxy /usr/lib/python2.6/site-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:90: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning. InsecurePlatformWarning You are using pip version 7.1.0, however version 8.1.1 i........

  • Nvidia Linux Card not working due to LSI 9200/SAS2008 IRQ conflict


    At first my BIOS said the card may not work right because there is no more option ROM space. I disabled the Option ROM for both LSI 1068 and 2008 chipsets, Network Boot ROM and most other PCI slots, Serial Port, etc... and the message went away but the card still does not work properly. But it still cannot initialize the card properly(does not work): [ 33.943272] NVRM: This PCI I/O region assigned to your NVIDIA device is invalid:........

  • Linksys E2500 DD-WRT Upgrade Instructions and Enabling 5ghz with Tomato Firmware


    1.) Flash directly to this file: http://tomato.groov.pl/download/K26RT-N/build5x-132-EN/Linksys%20E-series/tomato-E2500-NVRAM60K-1.28.RT-N5x-MIPSR2-132-Max.zip *I was never able to get the larger "Mega" file to work, at least not initially so I recommend the file above. To enable 5ghz I had to do the "Clear NVRAM" Option before it was shown. 2.) Or if you don't need 5ghz (most devices do not support it and cannot........

  • Errors were found while checking the disk drive for /.


    Iwill start by saying I think I know what caused this boot-time error on Linux Mint but should also apply to Debian and Ubuntu. I changed my BIOS time to several hours in the past to match the current time, but this caused Linux to think there were incorrect filesystem times. The problem is that it seems when you hit this I am not sure what is happening, it doesn't seem to be doing fsck and hangs without prompting the user. What I have found is that........

  • Avocent 8020 KVM Java Icedtea Viewer


    This command in Debian/Ubuntu/Mint will get everything need installed for most Java based KVM viewers: sudo apt install icedtea-netx The following additional packages will be installed: ca-certificates-java icedtea-netx-common openjdk-8-jre openjdk-8-jre-headless It seems every other updated version of Java or Icedtea breaks things and I will save the frustration of Java for another post.........

  • Virtualbox Error


    In plain English this happens after you upgrade VBOX and it rebuilds kernel modules based on a newer kernel than you are running (eg. you upgraded your kernel but haven't booted into it). It is too bad there is not a standard work around that would allow it to realize this and keep old kernel modules and use them if it detects your current kernel is older than the most recently build modules. =============== RTR3InitEx failed with rc=-1912 (rc=-1912) The........

  • 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 cannot login by console or ssh session closed immediately


    In my case I could login with the initial install but I rsync'd everything over while preserving ownership and permissions to another RAID partition and booted from that.was fine before. The problem is that you are kicked out the second you login and the problem was SELINUX for some reason (perhaps it noticed something strange when it was moved to the new partition) login: pam_unix(login:session): session opened for user root by LOGIN(uid=0) login: ROOT LOG........

  • 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........

  • initial Main Mode message received on 192.168.5.94:500 but no connection has been authorized with policy=PSK


    If you are getting this error from Pluto/IPSEC it is almost always due to a routing or NAT issue.........

  • 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 &........

  • 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........

  • KVM/QEMU how to boot from direct kernel vmlinuz and initrd with networking


    Thsi is very handy when doing your own kernel development. -m specifies how much ram (in the example it is 768MB) -kernel specifies the path to the kernel file -net tap,ifname=tap1,script=no (the ifname=tap1 is what you need to change and setup manually). *Run "tunctl -b" to create a tap device and use the one it gives you for ifname= Enable networking to the outside like this: *Note we assume that your bridge is br0 i........

  • OpenVZ vzctl update changes how iptables work - iptables v1.3.5: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. updated solution


    Are you getting the same old error message even though your iptables settings for OpenVZ are correct? iptables v1.3.5: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. The reason is because in newer vzctl the old way of setting IPTABLES="" in vz.conf is completely deprecated (I spent some time fiddling wondering why my settings were correct but........

  • Disable cphulk in CPanel if you can't login even with the right password


    It's a great feature to ward off bruteforce but is also annoying because you think you have the wrong password when you can't login. How to Disable cp hulk for 5 minutes /usr/local/cpanel/etc/init/stopcphulkd........

  • NS_ERROR_FAILURE (0x80004005) The virtual machine 'XP' has terminated unexpectedly during startup with exit code 1.


    The solution is to run '/etc/init.d/vboxdrv setup' and sometimes happens when upgrading VBox and the kernel modules don't get upgraded with it. Sometimes the above doesn't work until you reboot because sometimes other unknown processes (even the file manager possibly) may be locking the old module from being unloaded. Failed to open a session for the virtual machine XP. The virtual machine 'XP' has terminated unexpectedly during startup with exit code 1.........

  • Openvz iptables v1.4.7: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. solution


    iptables -t nat -A PREROUTING -p tcp -m tcp -d 192.168.2.1/32 --dport 3389 -j DNAT --to-destination 192.168.5.2:3389 iptables v1.4.7: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. The above is often because you don't have the correct modules loaded on the hostnode or enabled for the container but in some cases it's actually a weird openvz setting. Che........

  • Openvz 2014-08-12T19:05:55-0400 vzctl : CT 391801 : Unable to start init, probably incorrect template 2014-08-12T19:05:55-0400 vzctl : CT 391801 : Container start failed


    2014-08-12T19:05:55-0400 vzctl : CT 391801 : Unable to start init, probably incorrect template 2014-08-12T19:05:55-0400 vzctl : CT 391801 : Container start failed This was caused by trying to run a 64-bit template on a 32-bit kernel hostnode which is obviously impossible. The solution is to use a 32-bit template or upgrade the hostnode to 64-bit.........

  • drbd 8.3 hard drive failure recovery example


    drbd 8.3 hard drive failure recovery drbdadm attach r0 DRBD module version: 8.3.10 userland version: 8.3.8 you should upgrade your drbd tools! 0: Failure: (119) No valid meta-data signature found. ==> Use 'drbdadm create-md res' to initialize meta-data area. ........

  • drbd won't sync 8.3.13 on OpenVZ kernel


    I used the matching 8.3.13 utilities and it didn't work but strangely the newer 8.3.16 which makes DRBD complain works just fine. GIT-hash: 83ca112086600faacab2f157bc5a9324f7bd7f77 build by root@sighted, 2012-10-09 12:47:51  0: cs:SyncSource ro:Secondary/Primary ds:UpToDate/Inconsistent A r-----     ns:0 nr:0 dw:0 dr:0 al:0 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:b oos:5236960   &am........

  • Howto Convert Xen Image to KVM


    #count=10000 makes an image of 10000MB make sure your image is at least the same as your existing dd if=/dev/zero of=yourimage.img bs=1M count=10000 # losetup -fv newimage.raw # fdisk -cu /dev/loop0 # kpartx -a /dev/loop0 # dd if= of=/dev/mapper/loop0p1 # e2fsck -f /dev/mapper/loop0p1 # resize2fs /dev/mapper/loop0p1 # a lot of guides tell you to edit /etc/fst........

  • 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........

  • NVIDIA GeForce GT 610 not working in Linux solution - use older 304.117 driver


    Iused the slightly older "304.117" version and it worked. With the newest version Icouldn't get X to start and kept getting these errors in messages/dmesg. [ 2346.083660] nvidia 0000:01:00.0: irq 44 for MSI/MSI-X [ 2350.608342] NVRM: RmInitAdapter failed! (0x12:0x2b:1831) [ 2350.608354] NVRM: rm_init_adapter failed for device bearing minor number 0 [ 2350.608369] NVRM: nvidia_frontend_open: minor 0, module->open() failed, err........

  • Howto edit/rotate Samsung/Android Videos in mencoder solution


    Movie-Aspect is undefined - no prescaling applied. videocodec: libavcodec (720x1280 fourcc=34504d46 [FMP4]) [mpeg4 @ 0x2c91c00] timebase not supported by mpeg 4 standard Could not open codec. FATAL: Cannot initialize video driver. That is the error I would get, I thought it was a codec error something else. By fluke Isaw something about ffmpeg where someone recommended manually telling it to the "fps" and it worked.........

  • Linux Centos 6 Weird Kernel Panic


    Kernel panic - not syncing: Attempted to kill init! Pid: 1, comm: init Not tained: 3.2.51-3.el6.x86_64 #1 Call Trace: panic+0x8c/0x1a2 forget_original_parent+0x34d/0x360 exit_notify+0x12/0x140 do_exit+0x1d8/0x400 do_group_exit_+0x50/0xc0 sys_exit_group+0x12/0x20 system_call_fastpath+0x16/0x1b panic occurred, switching back to text console........

  • Asterisk iptables block bruteforce attacks howto with fail2ban


    yum -y install fail2ban vi /etc/fail2ban/jail.conf [asterisk-tcp] enabled = true filter = asterisk action = iptables-multiport[name=asterisk-tcp, port="5060,5061", protocol=tcp] sendmail-whois[name=Asterisk, dest=you@example.com, sender=fail2ban@example.com] logpath = /var/log/asterisk/messages maxret........

  • kvm centos cannot compile error


    ./configure ./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc yum -y install gcc make ./configure ./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc yum -y install compat-gcc-* ./configure Error: Could not find alsa Make sure to have the alsa libs and headers installed. yum -y install alsa-lib-devel ./configure........

  • Migrate Linux Mint OS from one drive to another


    mount -o bind /proc /sda2/proc mount -o bind /dev/ /sda2/dev mount -o bind /sys /sda2/sys chroot /sda2 mint / # mount -o bind /proc /sda2/proc mint / # mount -o bind /dev/ /sda2/dev mint / # mount -o bind /sys /sda2/sys mint / # chroot /sda2 mint / # cd ~ mint ~ # ls Desktop mint ~ # cd / mint / # ls bin Desktop dev-temp home&nb........

  • vzquota : (error) Quota on syscall for id 42131: No such file or directory vzquota on failed [3]


    Starting container... vzquota : (error) Quota on syscall for id 42131: No such file or directory vzquota on failed [3] Solution cd /var/vzquota mv quota.42131 quota.42131-disable vzctl start 42131 Starting container... Initializing quota ... Container is mounted Adding IP address(es): Setting CPU units: 1000 Container start in progress... ........

  • Apache SNI is not needed what is the issue?


    Iread this article and still don't understand the issue. If I understand correctly the client negotiates after the first SSLconnection and then gets the correct hostname and thus correct certificate. http://wiki.apache.org/httpd/NameBasedSSLVHostsWithSNI To their credit I know I'm not using SNIbecuase Iget this message in the Apache log :) [warn] Init: You should not use name-based virtual hosts in conjunction with SSL!! B........

  • 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........

  • yum update error


    yum update error 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", line 229, in user_main errcode = main(args) File "/usr/share/yum-cli/yummain.py", line 145, in main (result, resultmsgs) = base.buildTransaction() &nbs........

  • open /dev/kvm: No such file or directory failed to initialize KVM: Operation not permitted - Solution


    open /dev/kvm: No such file or directory failed to initialize KVM: Operation not permitted [ 96.084502] kvm: disabled by bios Any of the above means that "Virtualization" is not enabled in your BIOS. Most servers and Desktops (non-mainstream) can do this no problem but leave it off by default. Note that some systems even though the CPU supports it, don't allow enabling of Virtualization for some reason (especially some lap........

  • WD 20EARX 2TB Bad within days


    This is just trying to read 5GB off the drive with dd and the drive initially tested ok but shortly after I wondered why I was seeing 2MB/s read speeds. Notice the "current_pending_sector", anytime I've seen it at anything above 0 even with no other bad fields/attributes, it means the drive is bad. ata1.00: exception Emask 0x0 SAct 0x3 SErr 0x0 action 0x0 ata1.00: irq_stat 0x40000008 ata1.00: failed command: READ FPDMA QUEUED ata1.00: cmd 60/00:00:........

  • init: tty (/dev/tty2) main process (1031) terminated with status 1 init: tty (/dev/tty2) main process ended, respawning


    After some fsck issues I can't boot my Centos 6.4, this just keeps repeating over and over. init: tty (/dev/tty2) main process (1031) terminated with status 1 init: tty (/dev/tty2) main process ended, respawning Disabling SELinux through Single User mode fixed this.........

  • 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........

  • Kernel panic - not syncing: Attempted to kill init! Pid: 1,comm: init Tained: G I------------- 2.6.32-358.el6.x86_64 #1 Call Trace: [] ? panic+0xa0/0x16f [] ? do_exit+0x862/0x870 [] ? fput+0x25/0


    Kernel panic - not syncing: Attempted to kill init! Pid: 1,comm: init Tained: G I------------- 2.6.32-358.el6.x86_64 #1 Call Trace: [] ? panic+0xa0/0x16f [] ? do_exit+0x862/0x870 [] ? fput+0x25/0x30 [] ? do_group_exit+0x58/0xd0 [] ? sys_exit_........

  • 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........

  • Samsung Galaxy Note I717M Canadian Version, Root and Unlock


    I chose this because I heard a lot of stories about scams and that many providers I contacted said they can't unlock the Canadian I717s (one said "my Bell server" is down). This method worked perfectly on my Bell I717M and should work for all I717 in Canada, I was able to insert a foreign SIMcard. This will work abroad too but remember entering CWM mode is different for I717's in other countries (at least theUS). Step 1 - Root + CWM........

  • iptables v1.4.10: can't initialize iptables table `filter': Table does not exist (do you need to insmod?)


    I have iptable_filter loaded on the hostnode so I don't understand this issue.........

  • 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........

  • Setup PXE Boot using Centos and dhcpd, tftp and syslinux


    This is something I often setup for clients because it's very helpful for people in datacenters, this allows custom OS installs on demand, you can customize it more by using kickstart etc.. but here's a base I use before customizing more: This little script below will install everything you need to get booting by PXE Linux. It also assumes you set a local IP (be sure not to overwrite your existing IP) on eth0:0 (note the :0) as 192.168.1.10 and it........

  • 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........

  • iptables v1.3.5: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) - OpenVZ Container Problem iptables module problem solution


    iptables v1.3.5: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) This solution applies to all other iptables modules/problems for OpenVZ, you'll just need to add them to both lists/lines below if you have modules other than what I have below. The modules need to be enabled in both iptables and the OpenVZ hostnode itself and then the containers which need it must be restarted. How To Enable IPTables Modules in OpenVZ........

  • 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)........

  • 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........

  • vmware Failed to initialize monitor device 95% power on


    Failed to initialize monitor device 95% power on Solution /etc/init.d/vmware-core start........

  • Openvz migration error solution Error: Failed to suspend container CPT ERR: f68cf000,25000 :foreign process 15755/14731(vzctl) inside CT (e.g. vzctl enter or vzctl exec). CPT ERR: f68cf000,25000 :suspend is impossible now.


    Starting online migration of CT 25000 to 192.168.5.1 Preparing remote node Initializing remote quota Syncing private Live migrating container... Error: Failed to suspend container CPT ERR: f68cf000,25000 :foreign process 15755/14731(vzctl) inside CT (e.g. vzctl enter or vzctl exec). CPT ERR: f68cf000,25000 :suspend is impossible now. CPT ERR: f68cf000,25000 :foreign process 15755/14731(vzctl) inside CT (e.g. vzctl enter or........

  • How to recover from dead DRBD partition/hard drive in two simple commands


    This assumes that you've at least created the correct partition for your DRBD already. Notice that I am "diskless", that's because either your DRBD partition doesn't exist/has been renamed (eg. sdb becomes sda when sdb dies and you reboot) or because that drive is really actually dead/gone. *If you need to permanently change the partition/device for your resource be sure to edit /etc/drbd.conf on both hosts and reload the config. (replace r0 with........

  • 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........

  • monit example tutorial how to enable status checking and manipulation


    You need to enable the httpd daemon with monit to actually view the status and control, it's not only for the web interface since the httpd is theONLY way of controlling monit and viewing the status. monit monitor all will also reinstate disabled services if they've timed out too much. Just restarting the service will do nothing to re-monitor a service that monit has stopped monitoring due to too many failures. *Also note that /etc/monit.conf i........

  • Virpus Review/Scam/Complaint


    Virpus Review/Scam/Complaint Virpus is advertised on LEB (lowendbox.com). My initial payment was refunded after days of not receiving the VPS, but two subscrption payments went through and Ionly received notification after the second one. They ignored the requests in the ticket and by e-mail for a refund and even escalated the PayPal dispute that "we're assuming this is for a service that was provided" (when they obviously know otherwise by........

  • Linux - mptbase/MPT Fusion LSI Logic Error mptbase: ioc0: ERROR - didn't initialize properly! (-1)


    kernel 2.6.27.54 Fusion MPT base driver 3.04.07 Copyright (c) 1999-2008 LSI Corporation Fusion MPT SPI Host driver 3.04.07 mptbase: ioc0: Initiating bringup mptbase: ioc0: WARNING - Unexpected doorbell active! mptbase: ioc0: ERROR - Doorbell ACK timeout (count=4999), IntStatus=80000001! mptbase: ioc0: ERROR - Diagnostic reset FAILED! (102h) mptbase: ioc0: WARNING - NOT READY! mptbase: ioc0: ERROR - didn't initialize proper........

  • VPS Server Scam/Review/Complaint List


    These are the only two I've encountered but here is the low-end and note my story is not at all unique. In my case I was scammed out of money and did not receive any service at all from either company. Santrex Review/Scam/Complaint Santrex never provided any working server, I believe it was just a dummy management Solus server because the server said it was booted but never connected to the console. I complained to them and eventually the support adm........

  • 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........

  • ERROR! MySQL manager or server PID file could not be found! ERROR! Manager of pid-file quit without updating file.


    I found the cause of this issue was from all the diskspace being used but clearing it was not enough. Iguess the tables became inconsistent when space ran out and myisamchk is what fixed the rest. service mysqld restart ERROR! MySQL manager or server PID file could not be found! ....................................................................................... ERROR! Manager of pid-file quit without updating file. se........

  • How to see what's inside your gziped CPIO'd initrd image


    Copy the initrd to somewhere else, say /tmp: mv initrd.img to initrd.gz *the mv to .gz is needed otherwise gunzip won't work/it will refuse to operate without the correct .gz extension gunzip initrd.gz cat initrd | cpio -idmv The last command extracts the contents of initrd to your present working directory. For 7z .lz initrd........

  • Ubuntu/Debian DRBD 8.0 Setup Guide


    I've only used it on Centos, soI 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........

  • VMWare Server cannot connect to web interface SSL Handshake on client connection failed: SSL Exception


    VMWare log: /var/log/vmware/hostd.log SSL Handshake on client connection failed: SSL Exception sudo /etc/init.d/vmware-mgmt restart Stopping VMware management services: VMware Virtual Infrastructure Web Access VMware Server Host Agent&nb........

  • 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........

  • Initializing quota ... Error: Not enough parameters, diskinodes quota not set


    Initializing quota ... Error: Not enough parameters, diskinodes quota not set vzctl set $veid --diskinodes 90000:91000 --save New versions of OpenVZ seem to have some strange diskinodes parameter which is required.........

  • Revert to GRUB 0.97/1 instead of GRUB2


    had trouble trying to revert Ubuntu 10.04 LTS from grub2, won't boot mdraid and did not even install mdadm during the installation! I have tried moving back to GRUB 0.97 backed up original /boot and then copied /boot from an old Debian install. Modified device.map and menu.lst and put the appropriate kernels and initrd for Ubuntu back in /boot I ran grub: root (hd0,1) grub> setup (hd0) Checking if "/boot/grub/stage1........

  • Openvz Error Starting OpenVZ: failed to load module vzmon [FAILED]


    service vz start Starting OpenVZ: failed to load module vzmon [FAILED] vzmon: Unknown symbol ve_snmp_proc_init vzmon: Unknown symbol addrconf_sysctl_free vzmon: Unknown symbol ve_ndisc_init vzmon: Unknown symbol addrconf_ifdown vzmon: Unknown symbol ip6_frag_cleanup vzmon: Unknown symbol fini_ve_route6........

  • OpenVZ: failed to load module vzmon [FAILED] vzmon: Unknown symbol ve_snmp_proc_init vzmon: Unknown symbol addrconf_sysctl_free vzmon: Unknown symbol ve_ndisc_init vzmon: Unknown symbol addrconf_ifdown vzmon: Unknown symbol ip6_frag_cleanup vzm


    service vz start Starting OpenVZ: failed to load module vzmon [FAILED] vzmon: Unknown symbol ve_snmp_proc_init vzmon: Unknown symbol addrconf_sysctl_free vzmon: Unknown symbol ve_ndisc_init vzmon: Unknown symbol addrconf_ifdown vzmon: Unknown symbol ip6_frag_cleanup vzmon: Unknown symbol fini_ve_route6 ........

  • DRBD WFConnection Problem/Solution


    This has stumped me a few times because I keep forgetting that Centos 5.5 comes with a default iptables configuration that ends up blocking DRBD traffic,I tried all the normal things and couldn't understand why I couldn't make my normal DRBD config work. So if you have WFConnection problems and have tried the normal "mailing list" fixes, check your firewall status first! Both Nodes Say the Following: version: 8.3.8 (api:88/prot........

  • Installing Virtualbox on Centos 5.5


    wget http://download.virtualbox.org/virtualbox/3.2.8/VirtualBox-3.2-3.2.8_64453_rhel5-1.i386.rpm rpm -i http://download.virtualbox.org/virtualbox/3.2.8/VirtualBox-3.2-3.2.8_64453_rhel5-1.i386.rpm error: Failed dependencies: libGLU.so.1 is needed by VirtualBox-3.2-3.2.8_64453_rhel5-1.i386 libSDL-1.2.so.0 is needed by VirtualBox-3.2-3.2.8_64453_rhel5-1.i386 libXmu.so.6 is needed b........

  • Linux Kernel Freeze/Hang during boot on io scheduler cfq registered (default)


    You'll see the following and the boot process will freeze: io scheduler noop registered io scheduler anticipatory registered io scheduler deadline registered io scheduler cfq registered (default) I have struggled with this issue on vari........

  • OpenVZ iptables v1.3.5: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. Solution


    This error is annoying, in a Virtuozzo KB entry about this ip tables nat problem they say the kernel needs to be ugpraded: Symptoms The node runs 2.6.18-x kernel older than 2.6.18-028stab053.10. NAT module does not work in container, you get "can't initialize iptables table 'nat'" error: # iptables -t nat........

  • jailkit for chroot ssh account security tutorial and fix for error


    This was done on Centos butI think it's easier on Debian machines, the paths that it is set to use are tailored towards Debian, so there is some fiddling that needs to be done on Centos. This is for chrooting ssh, but jailkit has other uses than just SSH jails but I won't cover them in this writeup. 1. Install jailkit yum install jailkit 2. Setup Jail Home mkdir /home/jail chown root:root /home/ja........

  • 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 (althoughI 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........

  • 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).........

  • mdadm force/fix proper md127 name


    I have an md0 arary that my Centos install refers to. I feel this is half the reason why it won't boot anymore. I saw the initrd for Centos was assembling it as md127 even though it was known as md0. The reason for this is because I used mdadm --assemble --scan to detect the array on a LiveCD. I had no idea this name would stick (but now I realize the name is permanently stored in the metadata once you mount md127 or whatever random name assemble gives it). W........

  • MySQL Recover/Reset Lost/Forgotten root Password


    One note is to secure MySQL, I don't know for sure but I believe you could login to MySQL remotely with no password during this operation (I'm not sure, maybe it doesn't accept blank passwords but I firewall MySQL port anyway and recommend you do the same). First edit /etc/my.cf Under the [mysqld] field add the following line somewhere: skip-grant-tables Now restart mysql: service mysql restart or on Debian sty........

  • Centos 5.5 RAID 1 boot issue


    I installed 5.5 with a 300GB RAID 1 partition (boot is also on this partition). It booted up fine the first few times until after I used a Live CD and accessed the array, and it became named /dev/md127 for some reason. Now whenI boot into CentOS I get a kernel panic and different errors, once I got "invalid superblock", even though the array is fine (it didn't happen again, probably because I was sure to dismount and stop the mdadm array properly). Here's what........

  • 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 Iloved 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........

  • 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........

  • 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........

  • African money SCAM


    African money SCAMI have received countless of these sorts of emails where the person claims to be from an African nation which has a deposed finance minister or some other strange situation which puts millions of dollars at their disposal. The only problem is that they need a partner to get the money out. And they have entrusted only you, yes that's right, to donate your bank account information along with SIN number so they can secretly wire the money over and you w........

  • 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........

  • Mysqld Solution - Can't init databases /usr/libexec/mysqld: Can't read dir of '/tmp/' (Errcode: 13) /usr/libexec/mysqld: Can't create/write to file '/tmp/ibyP1qUC' (Errcode: 13) 100215 7:02:24 InnoDB: Error: unable to create temporary file; errno


    100215 07:02:24 mysqld started /usr/libexec/mysqld: Can't read dir of '/tmp/' (Errcode: 13) /usr/libexec/mysqld: Can't create/write to file '/tmp/ibyP1qUC' (Errcode: 13) 100215 7:02:24 InnoDB: Error: unable to create temporary file; errno: 13 100215 7:02:24 [ERROR] Can't init databases 100215 7:02:24 [ERROR] Aborting 100215 7:02:24 [Note] /usr/libexec/mysqld: Shutdown complete 100215 07:02:........

  • 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........

  • [error] server reached MaxClients setting, consider raising the MaxClients setting - Apache


    Have you ever seen this dreaded message in your Apache/HTTPD /var/log/httpd/error_log? [error] server reached MaxClients setting, consider raising the MaxClients setting The error itself is slightly misleading. Ibelieve this happened to one of my servers, I found Apache was running still, and that you could telnet to port 80 but no respnose would be given. For some reason my error log initially did not have the above error, but after a restart I saw........

  • How To Save iptables firewall rules Centos/Redhat/Fedora Linux


    This is something that annoys a lot of people, fortunately the Redhat style OS's are the most simple in this respect. I disagree that Debian's way makes sense, it is more of a hackish approach in how they implement iptables. Anyway, for those who are using Redhat/Centos style OS's it is very simple. Set your rules from the shell/command prompt and to save the iptables firewall rules so they are remember/loaded on boot just run this command: service iptables........

  • Using a Mac OSX DMG Image in Windows and Converting to Standard ISO Format use dmg2iso


    The dmg format is silly and annoying to work with, why couldn't Apple stick with the .iso standard? Anyway, there's an excellent Linux and Windows based tool to convert it back to a normal .iso Image called dmg2iso I'll only cover theLinux version although the Windows pre-built binary works the same way. Download dmg2iso here for free (from the author's website) It's just silly and doesn't make sense that Ubuntu doe........

  • RTL8111/8168B R8169 Gigabit Link slow speeds


    This is the Intel Atom 330 motherboard with integrated Realtek Gigabit NIC (Intel Desktop Board D945GCLF2 Motherboard W/ Atom 330 1.6 GHz Dual Core Processor - Mini-ITX) I cannot achieve more than 15 MB/s, even doing a local transfer through eth0 to it's own IP. 100% 95MB 15.9MB/s 00:06 So this is not a cabling, switch or hardware issue, it seems like a driver or chipset limitation problem. Here is my........

  • SSH Server Slow/Lagged/Delayed Login Response


    This is really something the SSHServer developers should consider. The cause of this annoyance is because of failed DNS lookups on your IPaddress, which is especially common for many dedicated/col-located servers and also computers on internal NAT/private networks. The chances are this is the cause of your SSHSlow/Delayed Login problems. The easy solution to SSH Login Problems Edit /etc/ssh/sshd_config Add this line to disable r........

  • SIOCSIFADDR No such device eth0 error while getting interface flags - eth0 Ethernet Device can


    Igot 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........

  • 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........

    • Latest Articles

  • Cisco CME How To Enable ACD hunt groups
  • How to install gns3 on Linux Ubuntu Mint
  • How to convert audio for Asterisk .wav format
  • Using Cisco CME Router with Asterisk as a dial-peer
  • Cisco CME How To Configure SIP Trunk VOIP
  • Virtualbox host Only Network Error Failed to save host network interface parameter - Cannot change gateway IP of host only network
  • Cisco CME and C7200 Router Testing and Learning Environment on Ubuntu 20+ Setup Tutorial Guide
  • Abusive IP ranges blacklist
  • How to Install Any OS on a Physical Drive from Windows Using VMware Workstation (Linux, Windows, BSD)
  • CDN Cloudflare how to set and preserve the real IP of the client without modifying application code on Apache
  • CentOS 7 fix Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=container error was 14: curl#6 -
  • Ubuntu Debian How To Install Recommended Packages Automatically
  • How to set Linux Ubuntu Redhat Debian Command Line http https socks proxy for yum apt
  • How to resize a pdf without losing much quality in Linux Mint Ubuntu Debian Redhat Solution
  • qemu: could not load PC BIOS 'bios-256k.bin' solution
  • Proxmox How To Custom Partition During Install
  • Hyper-V Linux VM Boots to Black Screen, Storage, NIC Not Found Issues
  • Ubuntu Mint How to Fix Missing/Broken /dev and /dev/pts which causes terminal to immediately close exit and not work
  • How high can a Xeon CPU get?
  • bash fix PATH environment variable "command not found" solution
    • Copyright © realtechtalk.com 2024