libvirt/virt-install

Prerequisites

libvirt, qemu, virt-install

On archlinux:

pacman -S virt-install libvirt qemu-desktop
pacman -S virt-manager # optional, graphical interface to libvirt
pacman -S qemu-emulators-full # optional, provides extra architectures emulation for qemu

systemctl enable libvirtd.socket # socket activation

Installing VMs

Archlinux

curl -O "https://mirror.checkdomain.de/archlinux/iso/2022.05.01/archlinux-2022.05.01-x86_64.iso"
virt-install --name archlinux                        \
            --memory 2048                            \
            --vcpus=2,maxvcpus=4 --cpu host          \
            --cdrom archlinux-2022.05.01-x86_64.iso  \
            --disk size=4,format=qcow2               \
            --network user                           \
            --virt-type kvm                          \
            --console pty,target_type=virtio         \
            --nographics

Follow the installation procedure. Edit the kernel cmdline and a serial console before rebooting otherwise the virsh serial console won't work:

In /etc/default/grub, add to the following to GRUB_CMDLINE_LINUX along with any other cmdline flags you require

GRUB_CMDLINE_LINUX=console=tty0 console=ttyS0,115200 # and any other flags

Update grub:

grub-mkconfig -o /boot/grub/grub.cfg

Nixos

curl -O "https://channels.nixos.org/nixos-21.11/latest-nixos-minimal-x86_64-linux.iso"
virt-install --name nixos                                   \
            --memory 2048                                   \
            --vcpus=2,maxvcpus=4                            \
            --cpu host                                      \
            --cdrom latest-nixos-minimal-x86_64-linux.iso   \
            --disk size=4,format=qcow2                      \
            --network user                                  \
            --virt-type kvm                                 \
            --console pty,target_type=virtio                \
            --nographics

Follow the installation procedure, adding the following to /etc/nixos/configuration.nix, otherwise the virsh serial console won't work

boot.kernelParams = [
    "console=ttyS0,115200"
    "console=tty1"
  ];

Ubuntu 21.10 (focal)

virt-install --name ubuntu-focal              \
             --memory 2048                    \
             --vcpus=2,maxvcpus=4             \
             --cpu host                       \
             --pxe                            \
             --disk size=4,format=qcow2       \
             --network user                   \
             --virt-type kvm                  \
             --nographics                     \
             --osinfo ubuntufocal             \
             --extra-args="console=tty0 console=ttyS0,115200" \
             --location http://archive.ubuntu.com/ubuntu/dists/focal/main/installer-amd64/

Other OSs

You can list other supported Operating Systems using

virt-install --osinfo list
# More info about available OSs
osinfo-query os

Note about serial consoles

In order for the virsh serial console to work, these kernel cmdline options have to be provided

console=tty0 console=ttyS0,115200

Usage

# list all available domains (running and stopped)
virsh list --all
# Start a domain ("archlinux")
virsh start archlinux
# Connect to the serial console
virsh console archlinux
# Destroy (destop) a domain ("archlinux")
virsh destroy archlinux
# Remove a domain
virsh undefine archlinux # disks will **not** be removed
# Edit a domain
virsh edit archlinux
# Get information about network configuration
virsh domifaddr archlinux

Note about serial consoles

Serial consoles might not work out of the box, so it might be required to edit the domain definition to add a serial console:

virsh edit <domain>

then add a pty console:

<console type='pty'>
  <target type='virtio' port='0'/>
</console>

Also see notes about serial consoles above.