KVM

From 太極
Revision as of 12:29, 2 December 2020 by Brb (talk | contribs) (→‎Resource)
Jump to navigation Jump to search

Resource

libvirt

  • https://en.wikipedia.org/wiki/Libvirt. libvirt is an open-source API, daemon and management tool for managing platform virtualization.[3] It can be used to manage KVM, Xen, VMware ESXi, QEMU and other virtualization technologies.
  • https://libvirt.org/
  • Check libvirt version: sudo head -n2 /var/log/libvirt/qemu/ubuntu2004.log # on Ubuntu 20.04 it shows 6.0.0

Bridge network

  • There are different ways to configure the network in Ubuntu.
    • If we are using a Ubuntu server, we will use the Netplan method.
    • If we are using a Ubuntu desktop, we will use the Network manager command line nmcli method or the GUI tool nm-connection-editor.
  • Use nmcli to add a bridge network and a bridge slave interface 
    sudo nmcli con add ifname br0 type bridge con-name br0
sudo nmcli con add ifname eno1 type bridge-slave master br0
  • Use nmcli to bring down a wired network and bring up a bridge network 
    sudo nmcli con down "Wired connection 1"
sudo nmcli con up br0
  • Use nmcli to delete unused bridge networks 
    sudo nmcli device show
sudo nmcli con show
sudo nmcli con del "br0"

Install

Install on Ubuntu

Install qemu-system-arm in Ubuntu

  • sudo apt install qemu-system-arm
  • How to emulate Raspberry Pi in QEMU which is based on qemu-rpi-kernel-Qemu kernel for emulating Rpi on QEMU. 
    mkdir rpi-vm && cd rpi-vm
git clone https://github.com/dhruvvyas90/qemu-rpi-kernel.git

# Download Raspbian Buster Lite
# from https://www.raspberrypi.org/downloads/raspberry-pi-os/
dd if=/dev/zero bs=1M count=4096 >> 2020-08-20-raspios-buster-armhf-lite.img

sudo losetup -f -P --show 2020-08-20-raspios-buster-armhf-lite.img

sudo mount -o rw /dev/loopXp2 /mnt

sudo nano /mnt/etc/fstab

sudo nano /etc/ld.so.preload # Comment out the line and save the file. 
# Then unmount with the following commands:
# sudo umount /mnt
# sudo losetup -d /dev/loopX

qemu-system-arm \
  -M versatilepb \
  -cpu arm1176 \
  -m 256 \
  -kernel qemu-rpi-kernel/kernel-qemu-4.19.50-buster \
  -hda 2020-08-20-raspios-buster-armhf-lite.img \
  -append "dwc_otg.lpm_enable=0 root=/dev/sda2 console=tty1 rootfstype=ext4 elevator=deadline rootwait" \
  -dtb qemu-rpi-kernel/versatile-pb-buster.dtb \
  -no-reboot \
  -serial stdio

# We can install a desktop. See 
# https://www.raspberrypi.org/forums/viewtopic.php?t=133691

Install on CentOS

snapshot

  • How to Create, Revert and Delete KVM Virtual machine (domain) snapshot with virsh command, How to create snapshot in Linux KVM VM/Domain 
    $ sudo su
# virsh list --all

# virsh snapshot-create-as --domain win10 --name win10_snap --description "Windows 10 snapshot"    # Create a snapshot
# virsh snapshot-list win10
# virsh snapshot-info --domain win10 --snapshotname win10_snap

# virsh snapshot-revert win10 win10_snap    # Restore

# virsh snapshot-delete --domain win10 --snapshotname win10_snap
  • To create a snapshot using the GUI, open virtualization manager window. In the VM properties, click on the icon (two displays overlapped) which is on the right of the menu, which says Manage VM snapshots.

GUI manager

Network

Back and restore images

How to KVM Backup and Restore in Linux 

# Backup 
virsh list --all
virsh dumpxml win10 > /MyBackup/win10.xml
sudo cp /var/lib/libvirt/images/win10.qcow2 /MyBackup/win10.qcow2
sudo chown $USER:$USER /MyBackup/*.qcow2

# Restore Making
sudo virsh undefine win10
ls -l /etc/libvirt/qemu
virsh list --all
sudo rm /var/lib/libvirt/images/win10.qcow2
sudo cp /MyBackup/win10.qcow2 /var/lib/libvirt/images/
sudo virsh define --file /MyBackup/win10.xml
# virsh start win10

Cheat sheet

KVM Cheatsheet

Run macOS on KVM / QEMU

How To run macOS on KVM / QEMU

Retrieved from "https://wiki.taichimd.us/index.php?title=KVM&oldid=27218"