• 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........

  • Hyper-V Linux VM Boots to Black Screen, Storage, NIC Not Found Issues


    Hyper-V uses obscure virtual hardware, you can enable the FB device for Hyper-V but if you just need text/console to work just compile this option: Device Drivers ---> Graphics support ---> Framebuffer Devices ---> Simpl........

  • 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........

  • 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........

  • nvidia cannot resume from sleep Comm: nvidia-sleep.sh Tainted: Linux Ubuntu Mint Debian


    This seems to happen in many different drivers but it happened more often in newer versions such as 530 vs 525. Then nvidia-modeset goes to 100% There are many reports of this appearing since driver 4.70 and I can confirm I've seen this in various machines. https://forums.de........

  • [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........

  • 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........

  • 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.........

  • Proxmox How To Rename Node Hostname Fix Solution


    Proxmox's documentation shows the following here. Which mainly just says change /etc/hosts and /etc/hostname with your new hostname. Here's what happens if you only do that: If you just do the above, you will find you have an inaccessible original hostname that contains those VMs and you cannot........

  • 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://........

  • Docker Minimum Requirements/How Efficient is Docker? How Much Memory Does Dockerd Use?


    We used a simple Debian 10 VM and showed the memory before starting docker and with no docker containers being started. The goal is to show much much memory dockerd actually uses. Before docker was started The VMwas using 58M of RAM. After docker was started it was using 99MB of RAM. How much RAM does docker use? It's not scientific but fair to say dockerd itself uses about 41MB of RAM (99-58).........

  • 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 echo as root solution to use tee permission denied solution Ubuntu Debian Mint Redhat CentOS


    The issue is when you need to echo something as root/sudo, that it doesn't work. You can never do a sudo echo to an output file as you'd expect. Take an example to clear out wasted RAM buffers/cache like this: sudo echo 1 > /proc/sys/vm/drop_caches -bash: /proc/sys/vm/drop_caches: Permission denied The solution is to run tee as sudo/root What we do is echo 1, but then pipe it to the "tee" command as sudo........

  • Linux swapping too much? How to check the swappiness and stop swapping


    We could always disable swap but this would normally be a bad idea unless you have an incredible amount of RAM and a workload that will never exceed it. However, for live/containerized and high performance environments it could be desirable. Another middle ground may be to set swappiness to a lower number. You may also want to clear your kernel's cache, which could be eating up RAM unnecessarily by c........

  • 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........

  • 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........

  • Dell PowerEdge Server iDRAC Remote KVM/IP Default Username, Password Reset and Login Information Solution


    Are you new to the company, datacenter or a third party who is responsible for deploying a fleet of servers from scratch. The first step is to normally login to the KVM so you can perhaps manually reinstall, PXE boot the Cloud Image or reimage/reinstall an OS but you need access to the KVM/IP or what Dell calls iDRAC. It's common that you may have forgotten this information or that another employee or colleague has changed the info and did not tell you, that they have left the........

  • docker / kubernetes breaks Proxmox QEMU KVM Bridge VMs


    Docker adds iptables rules that break a lot of things including MASQUERADE or anything that needs the FORWARD table. If NAT is not working after Docker installation, it is probably because it set the iptables FORWARD policy to DROP. This may also make you think that your br0 or bridge is not working, but it's likely just due to what we'll mention later on below, that, Docker probably set your FORWARD chain to default DROP all packets, so nothing on your bridge ever makes it out........

  • 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.........

  • 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........

  • 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:........

  • How To Enable Linux Swapfile Instead of Partition Ubuntu Mint Debian Centos


    This may be necessary if you have a VM or if for some reason you just want to be more efficient with your space and have the flexibility of changing your swap space at will. What we mean is the ability to use a "swap file" or similar to the Windows "pagefile" that normally resides on the root or c: partition of Windows. Here's all you have to do and then you to can have a single partiton with everything, including the swap file on the root partition if you........

  • WARNING: Can't download daily.cvd from db.local.clamav.net freshclam clamav error solution


    freshclam ClamAV update process started at Sun Mar 20 00:30:50 2022 WARNING: Your ClamAV installation is OUTDATED! WARNING: Local version: 0.100.3 Recommended version: 0.103.5 DON'T PANIC! Read https://www.clamav.net/documents/upgrading-clamav main.cld is up to date (version: 62, sigs: 6647427, f-level: 90, builder: sigmgr) WARNING: getpatch: Can't download daily-26337.cdiff from db.local.clamav.net WARNING:........

  • Vbox Virtualbox DNS NAT Network Mode NOT working


    There is a random bug that sometimes occurs with Vbox NAT mode DNS, although it has never happened in the past and Vbox was working fine until recently. The symptom is that you can see it does get an IP+ DNS from the Vbox NAT DHCP. Below we use resolvectl dns and verify the DNS server is set to 10.0.2.3 which is the DNS from Vbox NAT. We can ping it but it does not respond to any DNS requests when we use dig @10.0.2.3 realtechtalk.com........

  • 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.........

  • 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........

  • 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........

  • 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. ........

  • 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,........

  • Virtualbox Vbox Issue Cannot Enable Nested Virtualization Button is Grayed/Greyed Out and Unclickable HowTo Solution


    In newer of versions of Virtualbox, especially above 6.0 (eg. 6.1 like the example below), a lot of times the "Enable Nested VT-x/AMD-V". If you are having this issue, you will see the option is grayed out. It doesn't mean that your computer does not support virtualization, although it is possible it is disabled in the BIOS. You can verify........

  • Virtualbox VBOX Howto Port Forward To Guests


    NAT Network, the VMs can communicate but your host cannot access them by default. NAT VMs have internet but cannot communicate with each other. Bridged is simple and allows full LAN access as if you had a physical machine plugged in but is often bad for testing, work or corporate environments and is not very portable when it comes to moving your VMs to other locations and networks. Here is how you can use NAT Ne........

  • Linux Ubuntu Debian Centos Mint - How To Check if Intel VT-x or AMD-V Hardware Virtualization is Enabled?


    From the terminal do this: cat /proc/cpuinfo|grep -E "svm|vmx" You should get output like this(svm = AMD-v and vmx=Intel-VTx): flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqd........

  • Virtualbox VBOX How To Install Guest-Utils/GuestUtils so drag and drop and clipboard works Ubuntu Mint Debian Linux


    Just install these packages and restart the VM: 1.) Enable guest-utils on the host side: sudo apt install virtualbox-guest-utils virtualbox-guest-x11 2.) Enable guest editions on the VMside This must be done for each VM that you want to have the guest additons for accelerated GPU performance and for drag and drop/clipboard sharing First insert the Guest Addtions CD image........

  • 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........

  • 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........

  • VirtualBox VBox Nat Network Handing Out Wrong IP Address Subnet Solution


    This seems to be an ongoing issue that is still reproducable in the latest Ubuntu Vbox 6.x. The default NAT Network range is usually 10.0.2.0/24. If you change this range it does not seem to work properly. Say we change the range to 10.50.1.0/24 If you get a new lease you will find that you get an IP from the old range but the default gateway is from the new range. ........

  • 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........

  • QEMU KVM Keyboard Problems Not Working Right Repeating Characters, Ctrl+C Copy and Paste not working right when using PS2 mouse in guests Solution


    It seems that QEMU/KVM's default PS2 mouse and keyboard doesn't work right in most cases. I have especially observed issues using Ctrl+C and Ctrl+V and in Linux you may see repeated key presses in the terminal and you will wonder why you copied something and it's not in the clipboard when you try to paste. The way to temporarily fix it is to press the key that is repeating once(works in Linux but not really in Windows). Sometimes when moving your mouse it will also s........

  • Mikrotik RouterOS CHR/ISO Basic and Quick Setup Howto Guide


    Many people may not be aware that you can turn commodity hardware into a Mikrotik OS and there are various options which is "CHR" (Cloud Hosted Router) which is a VMimage meant for Virtualization only (seriously, I've tried to dd the image to a physical server and it just crashed as it does not contain any drivers for physical). One note as well if you are trying to do a baremetal install you may get an error "Error Loading Operating System" or........

  • qemu 4 compilation options


    How To Compile QEMU Manually (using sensible options) 1.) Download the QEMU source file you want. wget https://download.qemu.org/qemu-4.2.0.tar.xz 2.) Extract The Source File tar -Jxvf qemu-4.2.0.tar.xz 3.) Switch to the extracted source cd qemu-4.2.0 4.) Make sure we have the right libraries and tools to compile QEMU manually sudo apt install build-e........

  • 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.........

  • How To Boot, Install and Run Windows 2000 on QEMU-KVM


    Interestingly enough Windows 2000 works fine on QEMU 64-bit but you have to specify Pentium as your CPU otherwise it doesn't complete the install (it will not pass the detecting/setting up devices phase). -vga cirrus is wise because it is supported by Windows 2000 and allows higher resolutions and 24-bit color. -cpu Pentium emulates an old computer and is necessary for install to complete -device rtl8139 is important as this oldschool Realtek 8139 NIC is supported by W........

  • qemu-img convert formats vdi vmdk raw qcow2


    qemu-img can convert many formats. Here is an example of how to convert different images to different formats for QEMU-KVM The example above converts a raw windows2019.img file from QEMU to a Virtualbox .vdi qemu-img convert -f raw -Ovdi windows2019.img windows2019.vdi -f raw = this means the format of the source image (instead of raw it could be vdi, vmdi, qcow2 etc..)........

  • QEMU-KVM soundhw deprecated how to enable sound in QEMU 4.x series


    In QEMU 4 or higher you can no longer use the normal "-soundhw ac97" flag and it is much more complicated but here is a simple copy and paste on Linux that will just work: -audiodev you have to use -audiodev to specify the driver and id driver=pa id=someid -device you have to specify the same audiodev id you used in -audiodev and driver -audiodev driver=pa,id=pa1 -devic........

  • 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)........

  • How To Password Reset, Recover, Bypass, Remove and Unlock on Windows 10,8,7,Vista,XP,NT,2000,2003,2008,2012,2016,2019 Administrative Login Programs


    If you've come here, don't be embarraassed, working in IT, this is the MOST common computer problem that almost everyone will encounter. The reason why I'm doing this post is because I've seen an increase from colleagues and admins having this problem and many times it's not even your fault. A common scenario is that someone acquires a new or used computer which they weren't given the password for. Fortunately Ihave a detailed list of all the options whether free or pa........

  • ?? 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........

  • access denied by acl file qemu-kvm: bridge helper failed


    /usr/libexec/qemu-kvm -enable-kvm -boot order=cd,once=dc -vga cirrus -m 4096 -drive file=~/23815135.img,if=virtio -usbdevice tablet -net nic,macaddr=DE:AD:BE:EF:D4:AB -netdev bridge,br=br0,id=net0 qemu-kvm: -usbdevice tablet: '-usbdevice' is deprecated, please use '-device usb-...' instead access denied by acl file qemu-kvm: bridge helper failed [root@CentOS-82-64-minimal 23815135]# /usr/libexec/qemu-kvm -enable-kvm -boot order=cd,once=dc -vga cirrus -........

  • chroot


    chroot /root/kvmguests/4591915/mount FATAL: kernel too old This happens for example if you are in Centos 6 and trying to chroot into a system based on a newer kernel like 4.x+ You'll have to use a newer OS/kernel system to chroot into the environment or a VM running a newer kernel.........

  • 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 ........

  • QEMU-KVM KVM Command Line Practical Guide


    Iam going to build this based on a series of small howto QEMU / KVMposts I've made as I feel much of the information is actually hard to find and piece together from the rest of the web. What I'm going to focus on is how to use virtio as the NIC because if you don't you get very slow NIC speeds but with the virtio NIC model you basically get host speeds. /usr/libexec/qemu-kvm -enable-kvm -smp 8 -m 16000 -net user -net nic,model=virtio -drive file=ubuntu-gpt2l........

  • virt-resize: error: libguestfs error: could not create appliance through libvirt.


    This is caused because the user is running as qemu for virt-resize and if qemu does not have privileges to read from the source and write to the destination, it will fail with the below. So either change the uid of qemu or change the ownership of the source and target. Solution: export LIBGUESTFS_BACKEND=direct virt-resize --expand /dev/sda2 /root/kvmtemplates/windows2019-eval-template.img /root/kvmguests/kvmkvmuser4515........

  • QEMU KVM how to boot off a physical CD/DVD/BDROM Drive


    It's as simple as below where you just specify the dev device of the CDROM which is usually /dev/sr0. You can boot actual bootable discs like Windows, Linux, etc straight from a physical drive this way. sudo qemu-system-x86_64 -cdrom /dev/sr0 -m 4096 ........

  • OpenVZ vs LXC DIR mode poor security in LXC


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

  • Linux How To Add User To Additional Group


    sudo usermod -a -G groupname username It's really simple like above, the -a is for append so that you are not changing their main group, but adding them to another additonal group. Just change "groupname" to your group and "username" to the user you want to be added to "groupname". A common task these days is getting your user access to kvm for virtualization so the KVM/QEMUprocess........

  • 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........

  • KMODE EXCEPTION NOT HANDLED - QEMU/KVM Won't Boot Windows 2016 or 10 Image or Physical Machine


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    # first we need a physical volume which we use the pvcreate tool to create # I create mine on /dev/sdb3 pvcreate /dev/sdb3 dev_is_mpath: failed to get device for 8:19 Physical volume "/dev/sdb3" successfully created # pvdisplay shows the newly created volume pvdisplay "/dev/sdb3" is a new physical volume of "1.35 TiB" --- NEW Physical volume --- PV N........

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    ./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........

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  • 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........

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  • Directadmin Log File Locations


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    vgchange -ay 3 logical volume(s) in volume group "vg_12" now active lvscan inactive '/dev/vg_12/lv_root' [144.04 GB] inherit inactive '/dev/vg_12/lv_home' [1.00 GB] inherit inactive '/dev/vg_12/lv_swap' [7.85 GB] inherit........

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  • Startech SV1107IPEXT KVM/IP Review


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  • Lantronix KVM/IP Keyboard/Mouse not working in BIOS before booting the OS


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  • lvm resize and use the remaining extra space


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


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  • KVM compilation issue/solution - Disabling PIE due to missing toolchain support glib-2.12 required to compile QEMU


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    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........

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  • 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 ........

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  • vmware Failed to initialize monitor device 95% power on


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  • Linux Kernel Panic Messages - Symptoms of bad RAM module/stick


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    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........

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    You can't just do a straight copy of the VDI image of your virtual machine because there is a unique UUID, wellI believe you can and then you can create a new UUID manually (at least you could with VMWARE) but to keep it clean just use this method: VBoxManage clonevdi /path/to/your.vdi outputname.vdi 0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100% That's all there is to it, just wait for it copy and you can th........

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    I was afraid to remove the virtualbox 3.2 package in Ubuntu because I didn't know if it might remove the .virtualbox folder which contains all of my VM data. I have a backup soI did remove the package and found everything was intact, so I installed and upgrade to VBOX 4.0 which seems to be a huge improvement, especially in UI performance.........

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  • Virtualbox - Failed to open a session for the virtual machine XP. AMD-V is being used by another hypervisor. (VERR_SVM_IN_USE). - Solution


    Failed to open a session for the virtual machine XP. AMD-V is being used by another hypervisor. (VERR_SVM_IN_USE). VirtualBox can't enable the AMD-V extension. Please disable the KVM kernel extension, recompile your kernel and reboot (VERR_SVM_IN_USE) Solution - Unload KVM module (you can't use two hardware virtualization suites at once) sudo rmmod kvm_amd kvm........

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  • 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........

  • Ubuntu 9.04 Crash


    CPU/Kernel/MB/RAID problem? Jan 5 12:45:05 testbox kernel: [653298.890004] BUG: soft lockup - CPU#0 stuck for 61s! [hal-acl-tool:4168] Jan 5 12:45:05 testbox kernel: [653298.890005] Modules linked in: vmnet vmci vmmon binfmt_misc drbd video output input_polldev ocfs2_stackglue ocfs2_dlmfs ocfs2_dlm ocfs2_nodemanager configfs k8temp hwmon_vid lp snd_hda_intel snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_dummy snd_seq_oss snd_seq_midi snd_rawmidi........

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    VMWare bridged adapter not working: Message from system: The network bridge on device vmnet0 is not running. The virtual machine will not be able to communicate with the host or with other machines on your network. Failed to connect virtual device Ethernet1. I'm not sure how to fix this but one of the issues is that my eth0 became eth1 after moving my hard drives to a new motherboard. I have run the vmware-config.pl but this did not resolve the issue.........

  • SSH delay problem UseDNS and disabling GSSAPI does not help


    The normal solution doesn't help or apply here: ssh -v user@192.168.5.41 OpenSSH_4.3p2 Debian-9etch3, OpenSSL 0.9.8c 05 Sep 2006 debug1: Reading configuration data /etc/ssh/ssh_config debug1: Applying options for * debug1: Connecting to 192.168.5.41 [192.168.5.41] port 22. debug1: Connection established. debug1: permanently_set_uid: 0/0 debug1: identity file /root/.ssh/identity type -1 debug1: i........

  • 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.........

  • 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........

  • VMWare Server is on SSL port 8333


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  • PHP cannot access /usr/bin/openssl


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  • Updated to Version 3.8 and can't login


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  • PHPBB Drop All Tables


    PHPBB Drop All TablesSQL Syntax: [quote:75acd496c1]drop table phpbb_auth_access, phpbb_banlist, phpbb_categories, phpbb_config, phpbb_confirm, phpbb_disallow, phpbb_forum_prune, phpbb_forums, phpbb_groups, phpbb_posts, phpbb_posts_text, phpbb_privmsgs, phpbb_privmsgs_text, phpbb_ranks, phpbb_search_results, phpbb_search_wordlist, phpbb_search_wordmatch, phpbb_sessions, phpbb_smilies, phpbb_themes, phpbb_themes_name, phpbb_topics, phpbb_topics_watch, phpbb_user_group, p........

  • 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........

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    I've tried to find a good sensible solution to cluster with and each technology has it's pros and cons and there is no perfect solution and I've found a lot of "exaggerations" in the applications, benefits and performance of these different filesystems. DRBD I first started off with DRBD and Ihave to say it does live up to the hype, is quite reliable (although it can be annoying to match up the kernel module and user applications since they must match and whe........

  • Have an OpenVZ VPS/Linux Virtual Private Server and nothing works right?


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


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