Virsh Cheatsheet

Virsh is an extremely powerful tool for managing KVM/QEMU virtual machines. From restarting, to changing hardware, snapshotting, and cloning machines. I'll cover the basics of Virsh here, as it's all I personally use.

List VMs

virsh list

List all, including offline vms

virsh list --all

Start/Stop

virsh start $vm

virsh shutdown $vm

virsh reboot $vm

If the VM refuses to shutdown, etc. destroy performs an ungraceful shutdown

virsh destroy $vm

Autostart

virsh autostart $vm

virsh autostart $vm --disable

Rename

virsh domrename $vm $new_name

Delete

virsh undefine $vm

Delete Snapshots

If your VM has Snapshots it won't delete as simply, so delete those first

List the snapshots

virsh snapshot-list --domain $vm

And delete each snapshot with the following

virsh snapshot-delete --domain $vm --snapshotname $snapshot

Deleting with all storage

Delete the VM along with all the virtual storage

virsh undefine --domain $vm --remove-all-storage

Snapshots

Create

Save a snapshot of the VMs current state

virsh snapshot-create-as --domain $vm --name "$snapshot_name"

Restore/Revert

Revert the VM to the state it was in during the snapshot

virsh snapshot-revert $vm $snapshot_name

Delete Snapshot

Delete the snapshot, this doesn't delete anything else related to the VM

virsh snapshot-delete --domain $vm --snapshotname $snapshot_name

Drive management

Change Memory

In variantions of 512M, 1G, etc

virsh setmem $vm $ram

virsh setmaxmem $vm $ram

Change vCPU cores

This is a little more tricky, as it involves editing the XML file

virsh edit $vm

Then edit the vcpus section, change between the tags

<vcpu placement='static'>$vcpus</vcpu>

Connect via serial/console

This is a means to connect to your VMs via terminal

virsh console $vm

To do this you will likely need to first run the following command on the VM itself. This won't be required if you created the VM with console, but best to double check.

systemctl enable serial-getty@ttyS0.service