• Debian Ubuntu 10/11/12 Linux how to get tftpd-hpa server setup tutorial


    apt install tftpd-hpa #change TFTP_ADDRESS to by setting address to 192.168.1.1:69 or the IP you need, otherwise it will listen on all IPs and interfaces which could be a security risk. # edit /etc/default/tftpd-hpa TFTP_USERNAME="tftp" TFTP_DIRECTORY="/srv/tftp" TFTP_ADDRESS="192.168.1.1:69" TFTP_OPTIONS="--secure"........
  • efibootmgr: option requires an argument -- 'd' efibootmgr version 15 grub-install.real: error: efibootmgr failed to register the boot entry: Operation not permitted.


    This sometimes happens when trying to install the EFIversion of grub to a device when you are booted into Legacy/MBR mode. It doesn't seem to occur on all machines, but some and seems somewhat BIOS dependent. grub-install --target=x86_64-efi /dev/sda Installing for x86_64-efi platform. grub-install.real: warning: Couldn't find physical volume `(null)'. Some modules may be missing from core image.. grub-install.real: warning: Couldn't find physica........
  • zfs and LUKS how to recover in Linux


    Sometimes users take their removal drives and unplug and replug them to test what happens during the failure of a disk. However, this breaks things quite badly due to the /dev/mapper in LUKS not coming back online due to it not being closed. In other words, generally with non-encrypted drives the process is smooth but when encrypted you may want to follow a strategy like this: We can see below that both disks are unavailable as they were physically remov........
  • [error] (28)No space left on device: Cannot create SSLMutex Apache Solution Linux CentOS Ubuntu Debian Mint


    Have you got this error from Apache? [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec) [error] (28)No space left on device: Cannot create SSLMutex At first glance it appears that you may be out of disk space but the issue is ipc or interprocess communication. This will clear out the ipcs processes so things can work, this often happens during high traffic and may be a sign of DDOS. The command below will fix it, it will list al........
  • How to access a disk with bad superblock Linux Ubuntu Debian Redhat CentOS ext3 ext4


    Have you ever tried mounting a partition that you exists but you get this error? mount: /mnt: can't read superblock on /dev/sda1. The superblock in this example was bad because the physical disk had corruption and bad blocks/sectors. However, the data was generally accessible and you can always try this trick below (with caution and no warranty). This is specifically for filesystems that place superblocks in multiple locations, which........
  • ImageMagick error convert solution - convert-im6.q16: cache resources exhausted


    convert-im6.q16: DistributedPixelCache '127.0.0.1' @ error/distribute-cache.c/ConnectPixelCacheServer/244. convert-im6.q16: cache resources exhausted `/tmp/magick-27777Al6FGY7dhyKt10' @ error/cache.c/OpenPixelCache/3984. convert-im6.q16: DistributedPixelCache '127.0.0.1' @ error/distribute-cache.c/ConnectPixelCacheServer/244. convert-im6.q16: cache resources exhausted `/tmp/magick-277772Y_-pJnMdT2r1' @ error/cache.c/OpenPixelCache/3984. convert-im6.q16: Distr........
  • 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........
  • Proxmox install issue cannot see the buttons or install wrong / bad resolution cannot see the entire screen problem solution


    If you are using a hypervisor to test Proxmox (eg. Vbox) then changing the video card/display adapter can fix it. For example VboxSVGA causes the issue but switching to VMSVGA fixes it. For example VboxSVGA causes the issue but switching to VMSVGA fixes it. ........
  • 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://........
  • apache2 httpd apache server will not start [pid 22449:tid 139972160445760] AH00052: child pid 23248 exit signal Aborted (6) solution Mint Debian Ubuntu Redhat


    If you get this error, it is often because you have configured Apache with modules that weren't actually installed. Eg. you try to load the PHPmodule but didn't actually install the apache2 php module, so the server can't start. In general, this error can often be caused by issues with problematic modules and/or Apache being configured for modules that have not actually be installed (eg. libapache2-mod-php) is missing. The above results in this less than obv........
  • How To Setup Python3 in Ubuntu Docker Image for AI Deep Learning


    The issue is that Docker images are stripped down, so many tools and even python3 is missing, so you'll have to build or update the actual image yourself. I assume you have started an image with something like this and that you have the Nvidia Toolkit installed (assuming you are using GPUs). If you're not using nvidia just remove --runtime=nvidia --gpus all. docker run -it --runtime=nvidia --gpus all ubuntu bash These works for most images li........
  • How to Configure NVIDIA GPUs with Docker on Ubuntu: A Comprehensive Guide for AI Deep Learning CUDA Solution


    Welcome to our in-depth guide on configuring NVIDIA GPUs with Docker on Ubuntu. This post is tailored for developers, data scientists, and IT professionals who are looking to leverage the power of NVIDIA's GPU acceleration within Docker containers. Whether you're working on machine lea........
  • Linux How To Upgrade To The Latest Kernel Debian Mint Ubuntu


    How to check what kernel version you have/currently running? uname -rm 5.4.0-91-generic x86_64 The above shows us that we are running 5.4.0-91-generic on the x86_64 architecture. The safest way is to stick with the same flavor eg if you're on generic, and say on kernel 5.4.0 then it makes sense to follow what is below. However, if you are migrating or dual booting between newer hardware (eg. you got a........
  • 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,........
  • Virtualbox Best Networking Mode In Lab/Work Environment without using NAT Network or Bridged


    Virtualbox is a very powerful tool, but for some use cases it is less than optimal. Say you are in a work, lab or other environment where you are not alone on the physical network and there could be overlap of IPs, but you need all of your VMs to be contactable from your host, VMs need to communicate with each other, and VMs need internet. NAT Network will give you VM to VM communication and internet, however, it is buggy and unstable. It also doesn't allow host to VM co........
  • 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........
  • Linux grub not using UUID for the root device instead it uses /dev/sda1 or other device name solution


    You can read lots of posts about this issue but there is not much information about why this is the case or how grub determines the root= device name. Some even suggest modifying grub.cfg manually which is a disaster as the next kernel update will cause grub to revert back to the device name. For most people this won't be an issue but those using template system, automated deployments and working in embedded may run into this issue with custom embedded and created minimal kernel........
  • How To Restore Partition Table on Running Linux Mint Ubuntu Debian Machine


    Here is an easy way to restore things if you have the starting point and size of each partition using fdisk: In this example we pretend that /dev/sda was wiped out, but the running system still has the info in /sys/class/block/sda Go into each partition and record the "start" and "size" hostdev@box /sys/class/block/sda/sda1 $ cat start 2048 hostdev@box /sys/class/block/sda/sd........
  • 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........
  • 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........
  • GlusterFS HowTo Tutorial For Distributed Storage in Docker, Kubernetes, LXC, KVM, Proxmox


    This can be used on almost anything, since Gluster is a userspace tool, based on FUSE. This means that all Gluster appears as to any application is just a directory. Applications don't need specific support for Gluster, so long as you can tell the application to use a certain directory for storage. One application can be for redundant and scaled storage, including for within Docker and Kubernetes, LXC, Proxmox, OpenStack, etc or just your image/web/video files or even da........
  • How To Shrink Dynamically Allocated VM QEMU KVM VMware Disk Image File


    Let's say you have a VM file that uses 200G of dynamic space, but really only has 40G in usage. If you add fles and delete, at some point the file will be larger than the current space you are using. Take this image which shows is using 71G of space on the host: The actual space being used inside the image is about 43G as we can see:........
  • (firefox:9562): LIBDBUSMENU-GLIB-WARNING **: Unable to get session bus: Failed to execute child process "dbus-launch" (No such file or directory) Solution


    (firefox:9562): LIBDBUSMENU-GLIB-WARNING **: Unable to get session bus: Failed to execute child process "dbus-launch" (No such file or directory) ExceptionHandler::GenerateDump cloned child 9743 ExceptionHandler::WaitForContinueSignal waiting for continue signal... ExceptionHandler::SendContinueSignalToChild sent continue signal to child [Parent 9562, Gecko_IOThread] WARNING: pipe error (40): Connection reset by peer: file /build/firefox-EymEXX/fire........
  • Debian Mint Ubuntu Which Package Provides missing top, ps and w Solution


    Install procps and it will install the other packages you need: apt install procps Reading package lists... Done Building dependency tree Reading state information... Done The following additional packages will be installed: libgpm2 libncurses6 libprocps7 lsb-base psmisc Suggested packages: gpm The following NEW packages will be ins........
  • 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.........
  • 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........
  • Ansible Tutorial - Playbook How To Install From Scratch and Deploy LAMP + Wordpress on Remote Server


    1. Let's work from an environment where we can install Ansible on. If you are using an older version of Linux based on Mint 18 or Ubuntu 16, you may want to get the PPA and get the latest version of Ansible that way: sudo apt install gpg sudo add-apt-repository ppa:ansible/ansible sudo apt update........
  • Ceph Install Errors on Proxmox / How To Fix Solution


    This normally happens when you interrupt the install of Ceph: pveceph install update available package list start installation Reading package lists... Done Building dependency tree... Done Reading state information... Done gdisk is already the newest version (1.0.6-1.1). ceph-common is already the newest version (15.2.15-pve1). ceph-fuse is already the newest version (15.2.15-pve1). Some package........
  • QEMU/KVM How to Hot-add A Virtual Disk .raw/.qcow2 via QEMU Monitor Commands


    For a lot of reasons, it may be convenient to detach or attach live disks to a running VM without having to reboot it. Sure, you can use some network based storage, but when performance counts, attaching a new virtual disk will usually give you better throughput and lower latency in a quick testing situation. This doesn't work, why not? drive_add 0 if=virtio,file=/tmp/vm.qcow2,if=virtio,format=qcow2,id=rtt Can't hot-ad........
  • Proxmox How To Enable Ceph Distributed Storage Cluster with OSD and Pools


    How To Install Ceph If you stopped an install of Ceph midway you will need to manually restart it with "pveceph install" Remember that your VM needs to have working internet (gateway) and DNS in order to connect to the apt repo to download all of the packages that Ceph requires. Remember to repeat these steps for each node that you want Ceph on. ........
  • Proxmox Guide FAQ / Errors / Howto


    How To Enable HA in Proxmox Test Your HA Shutdown the node that has the HA VM. ........
  • Windows Cannot Format USB drive Device Media is Write Protected Error Solution


    First of all make sure that you don't have the write-lock or write-protect switch enabled on the SDCard or USB drive. If the above is not the case, then follow these instructions: Solution - Clear Read Only Attribute Hit "Windows Key+R" and enter "cmd" to enter the command prompt: Now type the following :........
  • Linux Mint 20 cannot install snapd missing solution


    The Linux Mint team has disabled it by setting an apt preference, you can edit or just remove the file: sudo apt install snapd Reading package lists... Done Building dependency tree Reading state information... Done Package snapd is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source........
  • How to install Kubernetes with microk8s and deploy apps on Debian/Mint/Ubuntu Linux


    Kubernetes Easy Beginners Tutorial/Architecture Guide Kubernetes is known as container orchestration and we should start at explaining the container part of it. A Container is what runs the actual application and based on an Image, and are more comparable to something like an LXC Container, Virtuozzo/OpenVZ using the Linux Kernel Namespaces feature. Containers run these images as independent, isolated operating environments under the O........
  • Linux How To Stop Missing Drive from Halting Boot Process in fstab


    When you automount a drive in /etc/fstab even if it's not important like an external drive that you only use sometimes and is not required for booting, it will prevent a successfuly boot. If you disable quiet mode for booting you will see something like below "A start job is running for dev-disk ...." How do we fix an fstab entry from preventi........
  • How To Setup a Cisco CME (Cisco Manager Express) Virtual Router under Linux using dynamips and dynagen


    This tutorial will get your router up and running using emulation tools. In this case we'll be getting a Cisco C7206 (C7200 series) VXR router going which also supports SCCP VOIP services. dynamips is the emulator itself and dynagen is the front-end tool that helps us control everything. It is used by tools such as gns3 and eve-ng. Together the two tools (dynamips and dynagen) allow us to create and emulate REAL router........
  • Virtualbox Error Cannot register the hard disk because a hard disk with UUID already exists solution


    Cannot register the hard disk '/some/path/windows-marking.vdi' {f54def00-2252-43f5-9178-0998636cad61} because a hard disk '/other-path/windows-marking.vdi' with UUID {f54def00-2252-43f5-9178-0998636cad61} already exists. Result Code: NS_ERROR_INVALID_ARG (0x80070057) Component: VirtualBoxWrap Interface: IVirtualBox {0169423f-46b4-cde9-91af-1e9d5b6cd945} Callee RC: VBOX_E_OBJECT_NOT_FOUND (0x80BB0001)........
  • ?? Question Marks for time, permissions and size of a file?


    -?????????? ? ? ? ? ? shadow ----------. 1 root root 748 Jul 10 04:35 shadow- cat: shadow: Input/output error If you see this you are probably in big trouble, it could be a physical error or if it's a VM image that it is corrupted due to a physical error on the underlying disk/array/NAS or it could a........
  • 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........
  • Linux How To Change NIC Name to eth0 instead of enps33 or enp0s25


    Most newer distros inexplicably cause your NIC to have what Icall "random" non-standard name conventions because of systemd. This is a big problem for many people and especially those running servers. Imagine that you have a static IPconfigured for ens33 but then the hard disk is moved to a newer system, the NIC could be anything from ens33 to enp0s1, meaning that manual intervention is required to go and update the NIC config file (eg. /etc/network/interfa........
  • Linux Debian Ubuntu How To Install PEPPER Faster and Latest Adobe Flash Player in Firefox


    Just run this apt install command sudo apt install pepperflashplugin-nonfree browser-plugin-freshplayer-pepperflash After this restart your browser and check Adobe's site to verify if your Pepper flash is working and showing at least version 32. https://helpx.adobe.com/flash-player.html As you'll see below it will download the latest version which is currently 32 and this was not possible with the old/crappy deprecated adobe-flash plu........
  • using Xvfb on virtual remote ssh server to have X graphical programs work


    The scenario here is that you have some sort of remote headless Linux server but would like to run some programs on them and get graphical access to them. The problem is that the remote server may be an image or VMwithout any virtual GPU and even if so, it is likely without KDE or Gnome, so there's no real way to do this, unless you follow our guide. Install xvfb apt install xvfb Reading package lists... D........
  • Convert and install to LUKS Encrypted Drive Ubuntu 18.04 19.10 Linux Mint and Debian Based Linux


    The reason for doing this is that the installer doesn't seem to work properly for LUKS and the server installer doesn't even support LUKS anymore. When you use the GUI install on Desktop for LUKS it won't boot and will just hang after you enter your password. So the only reliable way is to do it ourselves. 1.) Make a default minimal install of Ubuntu 2.) Have a secondary disk on the server or VM. 3.)........
  • CentOS 8 how to convert to a bootable mdadm RAID software array


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


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


    dd is a very handy tool and there are some more practical things we can do. For example if we want to dump a 3TB drive and want to preserve it and only 200GB are being used on the 3TB we can save a lot of space with gzip. Backing Stuff up with dd How to Use dd to backup a raw hard drive and tar gzip at once Change /dev/sda to the drive you want to backup Change /mnt/extras........
  • 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........
  • Linux Ubuntu Debian Centos How To Make a Bootable Windows 7, 8, 10, 2016, 2019 Server USB from ISO


    Use fdisk on your USB drive to create a bootable NTFS partition (in my case /dev/sdb): sudo fdisk /dev/sdb Welcome to fdisk (util-linux 2.27.1). Changes will remain in memory only, until you decide to write them. Be careful before using the write command. Command (m for help): n Partition type p primary (0 primary, 0 extended, 4 free)........
  • 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`........
  • 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........
  • Windows 7,8,10 and Server 2008, 2012, 2016, 2019 Read Only Attribute Won't Go Away


    I have seen this in a few rare cases after a reboot, where all folders and files will have the Read Only Attribute. If you uncheck it, it will just come back. It is more of a filesystem issue in Windows than a configuration issue and it looks like when Windows detects a badly corrupted filesystem that it will make things read-only, sort of like Linux would. If you are Administrator or the owner of the folder and this is happening it is probably due to the reasoning mention........
  • 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 ........
  • gsmartcontrol for Windows to Check the SMART S.M.A.R.T status


    gsmartcontrol is a free tool that let's you see the status of the SMART parameters so you can check things like temperature, reallocated sectors, bad sectors etc.. to give you a better idea of your drive health. Download it here. gsmartcontrol is a very useful tool in Windows to check your HDD / Hard Drive health status. In my experience you should NEVER trust that everything is OK just because SMAR........
  • chroot in Linux Howto Simple and Easy Guide


    chroot which stands for change root allows you to virtually operate in another operating system even though you haven't booted it. It is commonly used to deploy new distros, applications and to fix a broken Linux/Unix install or prep a new system image without having to physically boot the drive or disk. So in this example let's say we have a drive that has a Linux OS installed on /dev/sdb1 and we have mounted this partition on /mnt/sdb1 The key point is to edit the &quo........
  • How To Boot Cisco CUCM UCSInstall 8.6, 10, 11 and 12 on KVM/Proxmox


    The key thing is that you must use a "machine"id of "pc-1.3" or it will say your hardware is not supported. Additionally you MUST use a virtio disk or you will get a ks_pre.sh error as soon as the install starts (a look at logs will show it can't find a disk). This is funny because even though the OS finds the disk and an fdisk -l shows it, it looks like the script looks for a /dev/vda device (virtio) and nothing else, so if you didn't use Virtio as you........
  • VBOX VirtualBox How To Import Raw .img Disk File


    What you need to do if you have taken a dd or real raw image dump of a hard disk: VBoxManage convertdd windows2019-eval-template.img windows2019.vdi --format VDI The .img is the raw dd dump and the .vdi is the output file. --format VDIspecifies to output to .vdi format If you are in a pinch you can always use qemu-kvm binary and manually specify the .img as your disk and i........
  • LUKS Hard Drive Encryption on Linux Mint Ubuntu Debian etc how to mount encrypted hard drive


    The key thing here is to know the actual partition that is encrypted. Often in Linux Mint's installer that ends up being partition 5 or /dev/sda5 sudo cryptsetup luksOpen /dev/sda5 anynamehere You will then be prompted for your irrecoverable passphrase: Enter passphrase for /dev/sda5: If all goes well it won't say anything further. If it says ""No key available with this passphr........
  • LVM How To Create Pool (dynamically allocated and not fully allocated)


    The main use I have for this is virtual servers being able to use an LVM volume but not occupying all of the space. It saves time in deploying machines and copying them so you are only copying the space they are using (eg. 5GB / 60GB vs the full 60GB). There are some disadvantages which is mainly the fact that thin pools by their nature allow you to "overallocate" disk space which is that you could use more space than is available on the disk itself and corrupt your data........
  • Linux How To Create A RamDisk


    size = the amount of RAM (m for megabytes) /mnt/ram = the mount location of the ram disk (change to the path you want it mounted to) mount -t tmpfs -o size=4096m tmpfs /mnt/ram/ Example test in an old server: You can see that when reading if you don't specify bs1=M the read speeds are several times slower (eg. 450MB/s vs 2.1GB/s) mount -t tmpfs -o size=4096m tmpfs /mnt/ram/^C root@testserver:~# dd........
  • Proxmox Breaks Storage/LVM Backing If Killing QEMU-IMG


    I tried to stop a qemu-img copy or clone and it broke everything. It was fine to "stop" it from the GUI but a process still persisted so I killed the relevant qemu-img and the kernel went crazy. It also may not have helped that I tried to lvremove a different volume (an unused disk). But either way it breaks LVM (you cannot even run lvdisplay) so a reboot is necessary. Jan 17 06:45:21 testserver kernel: [ 5680.439337] systemd-udevd D 0&nbs........
  • Linux partprobe/partx cannot access last and 4th partition


    On a test machine Iwas never able to access to a newly created 4th partiton. As we can see there are dev devices for everything but the 4th partition. The normal "partprobe" or "kpartx" or kernel being told to rescan the block device didn't help (only a reboot did). fdisk -l /dev/sda Disk /dev/sda: 750.2 GB, 750156374016 bytes 255 heads, 63 sectors/track, 91201 cylinders Units........
  • Why SMART is not smart at all and doesn't properly predict disk errors that cause a kernel panic or crash


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    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........
  • mkdir: cannot create directory 'test': Disk quota exceeded - Solution


    mkdir: cannot create directory 'test': Disk quota exceeded You are out of inodes usually: df -i Filesystem Inodes IUsed IFree IUse% Mounted on /dev/simfs 200000 200000 0 100% / none ........
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    qemu-img create -f qcow2 isotest.qcow2 10G The above creates a "qcow2" format image called "isotest.qcow2" that is 10GB in size. If you want to preallocate all of the space for increased performance do this: qemu-img create -f qcow2 isotest.qcow2 -o preallocation=full 10G It is controlled with the preallocation=full option, of course by default this is set to off........
  • WD 20EARX Dead Again


    Another new drive bad from the start: Jun 2 15:14:18 one-desktop kernel: [15895.386779] ata2.00: exception Emask 0x50 SAct 0x1 SErr 0x280900 action 0x6 frozen Jun 2 15:14:18 one-desktop kernel: [15895.386782] ata2.00: irq_stat 0x08000000, interface fatal error Jun 2 15:14:18 one-desktop kernel: [15895.386784] ata2: SError: { UnrecovData HostInt 10B8B BadCRC } Jun 2 15:14:18 one-desktop kernel: [15895.386788] ata2.00: cmd 60/0........
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    Have you ever unplugged the wrong drive and then had to rebuild the entire array? It may not be a big deal in some ways but it does make your system vulnerable until the rebuild is done. Many distros often enable the "bitmap" feature and this basically keeps track of what parts need to be resynced in the case of a temporary removal of a drive from the array, this way it only needs to sync what has changed. To enable bitmap to speed up rebuilds and sync........
  • 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:........
  • SMARTCTL Enable SMART on Device Solution for Error "Device does not support SMART Error Counter logging not supported"


    smartctl -a /dev/sda smartctl version 5.36 [i686-pc-linux-gnu] Copyright (C) 2002-6 Bruce Allen Home page is http://smartmontools.sourceforge.net/ Device: ATA WDC WD1600YS-01S Version: 20.0 Serial number: WD-WCAP03024940 Device type: disk Local Time is: Mon Apr 29 21:40:07 2013 PDT Device does not support SMART Error Counter logging not supported........
  • vzquota : (warning) block_hard_limit [102] < block_current_usage [520824] - Openvz Solution


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


    Here's a proven example of what a bad hard drive can do, it was technically functioning OKin a RAID array but the system became extremely low and the load become high and IOWAIT was even higher and I always thought it was a bad application. The truth is that this failing 1TBHitachi has slowly gotten worse and caused huge slowdowns, (eg. 100% load on Thunderbird waiting for e-mails to load etc..). After swapping it out, tabs change instantly, emails are not lagged, and........
  • Samsung Galaxy Note ICS Corrupting microSDHC partition table?


    This was partitioned as a single 32GB VFAT but when I inserted it into the phone it said that it can't read it and now here is how the partition table looks. Interestingly enough the data works and reads fine from the computer still. Disk /dev/sdb1: 32.1 GB, 32085360640 bytes 64 heads, 32 sectors/track, 30598 cylinders, total 62666720 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum........
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    cat | grub --device-map=/dev/null Now pay close to the attention of the beginning. Type: "device (hd0) VPS.img" this is telling what hd0 will be to GRUB and we're telling it the disk image file "VPS.img" in the current directory is hd0, you can specify alternate paths and image names of course. GNU GRUB version 0.97 (640K lower / 3072K upper memory) [ Minimal BASH-li........
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    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........
  • KVM/QEMU Base/Template Images and the power they provide


    qemu-img create -b centos.5-8.x86.20120308.qcow2 -f qcow2 ../kvmguests/25000-centos5.8x86.qcow2 Formatting '../kvmguests/25000-centos5.8x86.qcow2', fmt=qcow2, backing_file=centos.5-8.x86.20120308.qcow2, size=10485760 kB -b the source/base image -f format is qcow2 and the location of the destination image What is so special about this? It's even quicker than creating a template with OpenVZ but this is an actual OS. It saves time a........
  • mdadm: /dev/sdb1 not large enough to join array solution


    mdadm --manage /dev/md1 --add /dev/sdb1 mdadm: metadata format 00.90 unknown, ignored. mdadm: metadata format 00.90 unknown, ignored. mdadm: metadata format 00.90 unknown, ignored. mdadm: /dev/sdb1 not large enough to join array md1's first primary member /dev/sda3 has 57394 cylinders while the /dev/sdb1 has 57393 (1 less cylinder) which is why it won't work. fdisk -l /dev/sda3 Disk /dev/sda3: 47........
  • How to mount/access a single partition from dd image with Linux


    parted sdc.img GNU Parted 1.8.8 Using /home/one/sdc.img Welcome to GNU Parted! Type 'help' to view a list of commands. (parted) unit&nb........
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    I backed up everything in the /mnt/sd_card directory thinking that some dataloss could occur for some reason but purposely left my microSDHC unbacked up thinking that "it won't touch that since it's external" and Samsung's and other manufacturers website even say this (that it won't be affected and not to worry etc). Apparently I was wrong, my microSD was "undetected" and asked to be formatted after the upgrade (there goes 3-months worth of family photos). No........
  • xen how to resize an image properly


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


    Disk /dev/sda: 320.0 GB, 320072933376 bytes 256 heads, 63 sectors/track, 38761 cylinders Units = cylinders of 16128 * 512 = 8257536 bytes Device Boot Start End Blocks Id System /dev/sda1 1 38........
  • Debian UUID not working


    Neither the blkid or the UUID internal to mdadm work to automount for some reason in Debian partprobe doesn't work but was a good suggestion from: http://pato.dudits.net/2008/11/03/special-device-uuidxxxxxxxxxxxxxxxx-does-not-exist-especially-with-lvm mount: special device /dev/disk/by-uuid/431b9b96-29e8f298-e89bd504-7065bddd does not exist mdadm -D /dev/md_d12 mdadm: metadata format 00.90 unknown, ignored. /dev/md_d12: &nb........
  • Windows Secret Hidden Temp Directory to free out of disk space issues


    Replace "Administrator" with your username. C:Documents and SettingsAdministratorLocal SettingsTemp Ihave often found several gigabytes of temporary files in there! Just be warned that they may not all be deletable if the files are being used by open programs (so close everything you can). This helped me in a pinch many times when for apparently no reason gigs of disk space are being used for an unknown reason.........
  • KVM QEMU and Xen how to mount disk images off-line and access data


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


    I dread updating the kernel and rebooting to find the Ubuntu graphics aren't working and you have to manually intervene. This is usually because Ubuntu for whatever reason didn't update the drivers you need (eg. the manually compiled Nvidia Kernel driver that MUST be recompiled for each and every kernel update unfortunately). The most common reason may be that "linux-source" hasn't been installed automatically on my system. I tried to manually reinstall the........
  • How To Burn ISO Image using cdrtools/dvdrtools for Linux/Unix Ubuntu/Debian/RHEL/Centos etc..


    It really is as simple as: cdrecord -v dev=/dev/sr0 pathtoyourisoimage.iso -v is for verbose, I prefer it but if you don't you won't see as much output like below (I like to know the details and exactly what's happening) dev=/dev/sr0 specifies the device name of your burner (they say not to use it and to specify some weird annoying device string but using the raw /dev has always worked for me and is how it should have been implemented from the start IMHO)........
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    Even in new versions of Ubuntu this happens but for me I found out it was because of one feature under "Power Management". I had "Spindown hard disks when possible" ticked, after disabling that, my computer wakes up from suspension every time now. So if your computer won't unsuspend with any version of Ubuntu/*Nix try disabling the spin down hard disk option as it's obviously the culprit for many situations.........
  • Hitachi HDD/Drive RMA Process Experience


    The first Hitachi Deskstar 2TB 5K3000 drive I bought arrived DOA for whatever reason (not recognized by the BIOS or OS). Perhaps it was shipping since I bought only 1 hard drive. When I bought 4 through another Vendor, all 4 checked out fine. I was worried about the RMA process because a lot of people have complained about Hitachi taking weeks to send out their hard drive and almost implied the warranty is useless. I'm happy to report that my experience was great a........
  • How To Test If Your Hard Drive Is Good/Signs of dying hard drive


    I like dd, although it only reads it, usually a read test of the entire disk will uncover if your hard drive is bad in some parts. This is a good thing to do at least once a month, a lot of times bizarre program behavior, laginess and crashing/unnmounting problems etc.. are due to a failing disc and SMART won't know it or indicate a problem: We must also remember there's never a guarantee, I've found that ever since we moved to larger and more platters per drive with 1TB drives........
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    I had a dying drive that smart thought until it totally disappeared was a good drive, and actually all parameters did look fine but this system was causing my system to lockup and other bad behavior: === START OF INFORMATION SECTION === Device Model: WDC WD20EARS-00MVWB0 Serial Number: WD-WMAZ20139 Firmware Version: 50.0AB50 User Capacity: 2,000,398,934,016 bytes Device........
  • Hitachi 2TB HDS5C3020ALA632 drive DOA


    I had one of these shipped and it was not recognized when plugged in, here's what a dead drive looks like (I assume it's teh circuit board which is dead): ata1: link is slow to respond, please be patient (ready=0) ata1: softreset failed (device not ready) ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300) ata1: link online but device misclassified, retrying ata1: link is slow to respond, please be patient (ready=0) ata1: softreset f........
  • How to recover from dead DRBD partition/hard drive in two simple commands


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    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........
  • VBox/Virtualbox how to shrink VDI image and recover/reclaim unused disk space


    VBoxManage modifyvdi /path/to/your.vdi compact I believe this should be done only when your VM is powered off, but I decided to try it with the system powered on. i wouldn't recommend it because it's dangerous even if it does work but this is a test system. For anything important/production I would always take a backup first and make sure the system is powered off. VBoxManage modifyvdi XP-clone.vdi compact 0%...10%...20%...30%...40%...5........
  • iPhone 3G/3GS/4 Undelete Photos/Videos Datarecovery


    I found this technique listed in many places which shows you how to use a common Linux tool "dd" to dump the raw partition of your iPhone. I give credit to this site for showing me the correct way to dd from the iPhone, I never thought to try it in the other direction:http://log.ijulien.com/post/182804914/iphone-3gs-data-recovery Requirements 1.) Jailbreak your........
  • Are my WDEARS20 Drives dying already?


    This happened during a RAID array check: SMART says both drives pass the test, but I'm doing a long test on them and hopefully this is not a hardware error. Apr 3 04:22:01 remote kernel: md: syncing RAID array md2 Apr 3 04:22:01 remote kernel: md: minimum _guaranteed_ reconstruction speed: 1000 KB/sec/disc. Apr 3 04:22:01 remote kernel: md: using maximum available idle IO bandwidth (but not more than 200000 KB/sec) for reconstruction. Apr........
  • CPU #1 not responding - cannot use it.


    I think this will be useful to others because I have a server that kept crashing mysteriously during intense disk usage/RAID checks. It would only crash during the weekly RAID integrity check. ThenI noticed during a reboot that not all CPUs were being brought up, as a result this actually creates much higher temperatures with the output I got from sensors, just booting the system produced higher than normal temperatures. You can imagine that a full blown RAID check........
  • Openvz Disk quota exceeded inode problem with free space


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


    Jan 16 04:02:03 centosbox syslogd 1.4.1: restart. Jan 16 04:07:34 centosbox kernel: INFO: task updatedb:20771 blocked for more than 300 seconds. Jan 16 04:07:34 centosbox kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Jan 16 04:07:34 centosbox kernel: updatedb D F78BE050 6476 20771 20766&n........
  • 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........
  • mdadm/md-check how to check array integrity without rebuilding


    This doesn't seem to be widely known (maybe it's in some documentation that none of us read though)but there's an easy way to check the integrity of any mdadm array: sudo echo check > /sys/block/md0/md/sync_action -bash: /sys/block/md0/md/sync_action: Permission denied sudo will never work, this only works as root since echo is not actually a binary/command. It is built-into bash. /sys/devices/virtu........
  • md: data-check of RAID array md3


    This really made me nervous but notice the mdstat says "check". This is because in Ubuntu there is a scheduled mdadm cronscript that runs everyday on Sunday at 00:57 that checks your entire array. This is a good way because it prevents gradual but unnoticed data corruption which Inever thought of. As long as the check completes properly you have peace of mind knowing that your data integretiy is assured and that your hard drives are functioning properly (I'........
  • WD EARS Advanced Format Can't be fixed?


    There's no partial WD EARS alignment fix: I had data on /dev/sda3 and /dev/sdb3 (RAID1) so I couldn't edit that one. I thought I'd be smart and try fixing the first two partitions so I set the first one starting at sector 2048 and then +8 for the second partition. This has really slowed the performance down worse than it ever was! Disk /dev/sda: 2000.4 GB, 2000398934016 bytes 255 heads, 63 sectors/track, 243201 cylinders, tot........
  • vmare server - Cannot open the disk '/mnt/sda4/vmware/Debian/hdd.vmdk' or one of the snapshot disks it depends on. Reason: Failed to lock the file.


    Go into the directory for your Virtual Machine and delete all ".lck" directories. rm -rf *.lck After that your server should boot.........
  • 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........
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    I wanted to Import/Use a .vmdk hard disk image file from VMWare. Generally you can just "point" VirtualBox to it and use it and it will work but I found an exception. One of my Centos 4.4 x64 images wouldn't boot. I had two copies, an older one and the newer one. The older one booted as normal (once I changed the VirtualBox driver to IDE from SATA). The newer one stopped at the "GRUB loading" message no matter what I tried. As far as........
  • vzquota : (warning) Incorrect quota shutdown for id 2333, recalculating disk usage vzquota : (error) quota check : lstat `sess_a5078fce5f569e453ab1fb39b0fc69f8': No such file or directory vzquota on failed [1]


    first container would not come up: Starting CT 2333: service vz stop OpenVZ is locked [FAILED] 2010-11-29T23:26:23-0800 vzctl : CT 2333 : Starting container ... 2010-11-29T23:37:21-08........
  • WD EARS/Green 2TB Cannot Disable Power Saving/Head Parking with hdparm


    hdparm -B 255 /dev/sdb /dev/sdb: setting Advanced Power Management level to disabled HDIO_DRIVE_CMD failed: Input/output error The one thing you can do though is to set hdparm spindown time lower (it doesn't seem to work that well). -S set standby (spindown) timeout hdparm -S 251 /dev/sda /dev/sda: setti........
  • mdadm RAID 1 adventures


    I separated the 2 drives in the RAID 1 array. 1 is the old one /dev/sda and is out of date, while the separated other one /dev/sdc was in another drive and mounted and used with more data (updated). I wonder how mdadm will handle this: usb-storage: device scan complete md: md127 stopped. md: bind md: md127: raid array is not clean -- starting background reconstruction raid1: raid set md127 active with 1 out of 2 m........
  • WD (Western Digital) Advanced Format Drive Lagged/Slow Speed/Performance/Design Flaw EAD/EARS problem WDC WD20EARS-00S8B1


    Let the numbers speak for themselves, from what I read the Load_Cycle_Count which is very high (more than 500,000/half a million times) is the number of head parks. What a stupid"Green" design and design flaw which will probably mean an early life for the drive. This is almost as silly as Seagate's new reputation for BSY/poor quality disks since the 7200.11 series. To make it worse this is also when Western Digital introduced "Advanced Format" o........
  • 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........
  • Wine stopped working/won't work Solution


    After an upgrade wine wouldn't open anything, not even the pre-installed notepad. There are no wine logs and nothing is mentioned in any standard log file about why. I finally decided to run wine from the shell and see what's going on: wine client error:0: version mismatch 398/402. Your wineserver binary was not upgraded correctly, or you have an older one somewhere in your PATH. Or maybe the wrong wineserver is still running?........
  • Buffer I/O error on device fd0, logical block 0


    Virtually no system has a floppy disk drive anymore but you will often find your Linux distribution insists that you do or should have one :) The solution is to remove the floppy module and prevent it from loading on the next reboot. rmmod floppy Centos/RHEL echo "blacklist floppy">> /etc/modprobe.d/blacklist #update initramfs so it takes effect dracut........
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  • SolusVM/Xen Central Backup Warning - Takes System Off-line!


    This really gives me a bad impression of SolusVM. I tried the "Central Backup" option and it does not warn that your server gets shutdown instantly in order to do the backup! Further, there is no way to pause or cancel the backup. Thankfully this is a test/small disk usage VPS but what if someone was running something production with a large filesize? Ihaven't used QuickBackup but hope that isn't the same thing. Everyone should be vary car........
  • 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........
  • VirtualBox Error Failed to start the virtual machine Centos 5.5 Mirror. Medium '/home/testuser/.VirtualBox/HardDisks/Centos 5.5 Mirror.vdi' is not accessible. UUID {a1a9fad7-0402-4867-b8f3-39fb49454bc5} of the medium '/home/testuser/.VirtualBox/HardD


    Virtualbox Error I tried to copy a .vdi of one container to use in another one, basically to clone instead of having to install the OS again. Failed to start the virtual machine Centos 5.5 Mirror. Medium '/home/testuser/.VirtualBox/HardDisks/Centos 5.5 Mirror.vdi' is not accessible. UUID {a1a9fad7-0402-4867-b8f3-39fb49454bc5} of the medium '/home/testuser/.VirtualBox/HardDisks/Centos 5.5 Mirror.vdi' does not match the value {4945a0e8-0ed5-4736-9088-bcaf........
  • md: kicking non-fresh sda1 from array! - fix/solution


    md: Autodetecting RAID arrays. md: autorun ... md: considering sdb1 ... md: adding sdb1 ... md: adding sda1 ... md: created md0 md: bind md: bind md: running: md: kicking non-fresh sda1 from array! md: unbind md: export_rdev(sda1) raid1: raid set md0 active with 1 out of 2 mirrors The md0 raid kicked sda1 ou........
  • Install Mac OS X 10.4.6 Tiger on AMD32 VMWare


    *Note OS X is strange to install, I thought my HDD was not being detected by you just have to go to Diskutil and create a partition for the root filesystem and then close/move the Window and proceed with the install. After install Mac OS X 10.4.6 Tiger I get a black screen that says: b0 error Most people say the partition has to be marked as "active", actually that just means marked as "bootable". Instead of t........
  • 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........
  • mdadm: /dev/sda1 is too small: 0K - solution


    I was creating a RAID array and got this error: mdadm: /dev/sda1 is too small: 0K mdadm: create aborted Of course sda1 is not too small, both partitions sda1 and sdb1 are identical in size: Disk /dev/sda: 2000.3 GB, 2000398934016 bytes 255 heads, 63 sectors/track, 243201 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x00000000 Device Boot Sta........
  • Unixbench Score on Core i5 750 with OpenVZ Kernel vs Xen/Openvz


    This was unbelievable how much the Xen kernel slows things down, keep in mind both tests were done on the hostnode, one was with the Openvz-Xen hybrid kernel and the other was just OpenVZ. You can see the performance difference is nearly 300% better when not using the Xen kernel. OpenVZ-Xen Kernel Test Results (I was wondering what was wrong/so slow with my Core i5!) # # # # # #&n........
  • chroot into an off-line Linux version using a LiveCD/USB


    It's not just as simple as running the chroot command, you need to ensure the /proc and /dev entries are passed through and populated to the chroot environment. Step 1 - Mount Your Off-lineOS mount /dev/sda1 /mnt Step 2 - Mount Proc mount -t proc none /mnt/proc Step 3 - Mount Dev Most guides will tell you to use this: mount -o bind /dev /mnt//dev but that doesn't work for some reason in many cases: mount: wron........
  • Seagate Drive 500GB Drive Dying


    This drive is clearly on the way out, the Kernel knows it but I'm surprised that SMART is not concerned. I didn't blame Seagate for their past issues until now. This hard drive has hardly been used and has not even been powered on for a year according to SMART. Home page is http://smartmontools.sourceforge.net/ === START OF INFORMATION SECTION === Model Family: Seagate Barracuda 7200.11 Device........
  • Seagate 7200.11 firmware defect in 500GB, 1000GB (1TB) and 1500GB (1.5TB) Hard Drives


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  • Linux AHCI Hotswap Tips - Remember To Reread The Partition Table WITHOUT rebooting


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  • 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........
  • Monitor MB/s Disk IO Usage/Bandwidth - Use iostat from the sysstat Package


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  • Rsync Timeout/Stall On Large files bigger than 16GB/Cannot Transfer large files with rysnc


    The last transfer I was able to do was 16.77GB according to rsync's output and it worked fine. 16.77G 100% 10.66MB/s 0:25:00 (xfer#17484, to-check=234753/256249) But on a file over 17GB (gigs) it stalls. Trust me, it really is stalled, it's been about 8 hours with no progression from that point for some reason. 17.24G 54% 10.65MB/s 0:22:07........
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  • Picking an FTPD (vsftpd) Server in Linux Centos/Debian


    I decided on using yum to help me decide even though I normaly use proftpd I decided to see what else I could find. yum search ftp Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * rpmforge: ftp-stud.fht-esslingen.de * base: mirrors.netdna.com * updates: updates.interworx.info * addons: yum.singlehop.com * extras: mirrors.netdna.com rpmforge........
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    ./ntfs-3g /dev/sda1 /mnt -o force Unexpected sectors per cluster value (127). Failed to mount '/dev/sda1': Invalid argument The device '/dev/sda1' doesn't seem to have a valid NTFS. Maybe the wrong device is used? Or the whole disk instead of a partition (e.g. /dev/sda, not /dev/sda1)? Or the other way around? This is happening on a system I've come across an HP 6930P running Windows XP Professional. The partition appears to be very norm........
  • Compaq V2405CA Laptop - Unixbench Performance Test


    Here are the results, it is Sempron 3000+ AMD Mobile, 500Gig HDD, 512MB RAM with shared ATI Radeon graphics. # # # # # # # ##### ###### # # #### # # # # ## # # # #&nb........
  • heartbeat is stopped for some reason


    heartbeat is stopped for some reason Anyway hnode2 was active and the services are running fine but I see heartbeat has been stopped somehow. Here is the last log I see of heartbeat: [quote:23c84415f5] Sep 9 17:15:32 hnode2 heartbeat: [16738]: info: MSG stats: 9/1762471 ms age 0 [pid16738/MST_CONTROL] Sep 9 17:15:32 hnode2 heartbeat: [16738]: info: cl_malloc stats: 716/51784021 152624/74519 [pid16738/MST_CONTROL] Sep 9 17:15:32........
  • rsync bash script


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  • Clone any OS partition perfectly


    Clone any OS partition perfectlyIn one box I needed to copy the boot partition to another disk while retaining the MBR and other data. I simply ran this command: [code:1:1b1ff110ca]dd if=/dev/hda1 of=/dev/hdb1[/code:1:1b1ff110ca] [b:1b1ff110ca]if[/b:1b1ff110ca] = source patition [b:1b1ff110ca]of[/b:1b1ff110ca] = destination partition Here's an interesting article on it http://www.rajeevnet.com/hacks_hints/os_cl........
  • Mount Linux ext2 file system


    Mount Linux ext2 file systemNormally in Linux you could mount ext2 or ext3 etc... like this: mount -t ext2 /dev/hda1 /mnt/hda1/ In FreeBSD the difference is of course the disk naming conventions (hda1 would be known a /dev/ad0s1): To mount ext2 in FreeBSD just type: mount -t ext2[b:68c16c60bf]fs[/b:68c16c60bf] /dev/ad0s1 /mnt/ad0s1........
  • The New Chips on the Block


    The New Chips on the BlockThe New Chips on the Block By Bruce Gain Story location: http://www.wired.com/news/infostructure/0,1377,67795,00.html 02:00 AM Jun. 13, 2005 PT We have embarked upon a new era in x86 PC computing -- so say chip giants AMD and Intel following their launches of dual-core PC processors. So how will dual-core processing change your PC computing experience? Our FAQ should help you decide whether or when you sho........
  • 100% disk usage for no apparent reason!


    100% disk usage for no apparent reason!I have a full disk and need to find out which files are taking up too much space!........
  • View Disk Space Usage sorted by the size


    View Disk Space Usage sorted by the sizeUse: [code:1:8f675c5910]du -h | sort -n[/code:1:8f675c5910] The -h in du makes it show Kbytes or Mbytes instead of just bytes making it easier to read. The sort -n will show the files in order of smallest to largest *Note if you specify sort -nr instead then it will show the largest files first.........
  • Clustering Links


    Clustering LinksI thought this might be interesting for people with spare time. [b:6423c19973]Great clustering article from Linux Mag[/b:6423c19973] http://www.linux-mag.com/2003-11/clusters_01.html [b:6423c19973]General Linux cluster information[/b:6423c19973] http://www.gdargaud.net/Hack/ClusterNotes.html#HighA http://www.faqs.org/docs/Linux-HOWTO/Cluster-HOWTO.html#s3 http://www.yolinux.com/TUTORIALS/LinuxClustersAndFileSys........
  • SATA Power cable for 1U Server Solutions - Rosewill 8" SATA Power Cable Model RC-8"-PW-4P-2SA


    NewEgg is one of the few companies that stocks this great right angle 1U SATA power cable. I've purchased some no-name ones and they face the wrong way (towards the bottom of the chassis) which makes it worse/impossible than standard SATA connectors. The price is high but if you're building a 1U server and want SATA disks and don't have much space (eg. the 1U Supermicro cases) then these are simply a must and........
  • How to Track Down/Find Cause of Linux high disk iowait/wa


    top - 09:34:12 up 2 days, 20:57, 2 users, load average: 1.83, 1.99, 2.03 Tasks: 59 total, 2 running, 57 sleeping, 0 stopped, 0 zombie Cpu(s): 0.3%us, 0.0%sy, 0.0%ni, 0.0%id, 99.7%wa, 0.0%hi, 0.0%si, 0.0%st That 99.7% wa is iowait, it means the server is waiting for a process to complete an IOoperation or in plain English, there is a delay in........
  • Tyan S2735-8M Maximum Hard Drive Limit/Not Working/Doesn't work with 1TB 1000GB hard drives


    Inever saved any of the logs, but basically no matter what OS (Linux)I used, I could not get my 1000GB hard drive to work (Seagate SATA). The BIOS recognizes the drive and fdisk -l shows the hard drive as it should. The tricky thing is that different OS's will give you different results, but don't be fooled. You can't use these larger drives for long. Iwas getting all kinds of seek/IOerrors and also messages that the port could not be read.........
  • Viewing and Connecting to an SMB Samba Share on Windows/Linux/Unix


    This will give you the basic info needed to browse and connect to Samba shares from the command line. From the GUI of Gnome or KDE etc, it is pretty standard and straight forward. However, I've found very little guides on how to do it from the command line and if you're like me, a nerd who prefers command line for its simplicity and for remote use, this is the way to go. First get a list of all the Samba/SMB shares on the target. smbclient -L hostname........
  • Rackable Systems and their Microslice Clustered 1U Servers


    Ithink there has been a lot of negative press towards Rackable Systems. We will give their new solution credit that it is marketed very well, and comes prepackaged and ready to go. But let's cut through the hype of both sides, the people who love this concept and the people who hate it. What Rackable Systems have done is a first, to minimize space, power and costs into small servers. This is great, and many companies have already built their own servers based........
  • Writing/Burning a data CD-R/DVD-R or DVD+RW in Unix/Linux


    There's a lot of outdated information and confusion for system administrator's out there. One annoying task for many an Administrator has been backing up data in Linux. You don't need any GUI tools such as K3B or GnomeBaker. Both are excellent tools but for veteran command line users working remotely, using the keyboard is a great and possibly automated way to save yourself pain and hassle. At a later date we'll cover how scripting can automatically backup certain........
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