QEMU
2024-10-24
Take snapshot of VM
sudo virsh domblklist vm1
Target Source
-----------------------------------------------
vda /var/lib/libvirt/images/vm1.img
sudo virsh snapshot-create-as \
--domain vm1 \
--name guest-state1 \
--diskspec vda,file=/var/lib/libvirt/images/overlay1.qcow2 \
--disk-only \
--atomic \
--quiesce
Ensure qemu-guest-agent is installed inside the VM. Otherwise omit the --quiesce flag, but when you restore the VM it will be as if the system had crashed. Not that big of a deal since the VM’s OS should flush required data and maintain consistency of its filesystems.
sudo rsync -avhW --progress /var/lib/libvirt/images/vm1.img /var/lib/libvirt/images/vm1-copy.img
sudo virsh blockcommit vm1 vda --active --verbose --pivot
Full disk backup of VM
Start the guest VM:
sudo virsh start vm1
Enumerate the disk(s) in use:
sudo virsh domblklist vm1
Target Source
-------------------------------------------------
vda /var/lib/libvirt/images/vm1.qcow2
Begin the backup:
sudo virsh backup-begin vm1
Backup started
Check the job status. “None” means the job has likely completed.
sudo virsh domjobinfo vm1
Job type: None
Check the completed job status:
sudo virsh domjobinfo vm1 --completed
Job type: Completed
Operation: Backup
Time elapsed: 182 ms
File processed: 39.250 MiB
File remaining: 0.000 B
File total: 39.250 MiB
Now we see the copy of the backup:
sudo ls -lash /var/lib/libvirt/images/vm1.qcow2*
15M -rw-r--r--. 1 qemu qemu 15M May 10 12:22 vm1.qcow2
21M -rw-------. 1 root root 21M May 10 12:23 vm1.qcow2.1620642185