Test a virtual machine restore
A backup counts only after you boot a copy on storage and a network that cannot reach production.

Pick one representative guest each quarter: a domain controller alternative, a database, and a file server cover most failure modes. Restore them to an isolated host or VLAN. Confirm the operating system boots, the application starts, and a recent record is present.
Time the restore. That duration is your real recovery time, not the vendor brochure. Write the date, the job name, the person who watched the boot, and any missing driver or VLAN.
The check below only proves a file is present. The boot test proves the backup.
#!/usr/bin/env bash
set -euo pipefail
archive="/var/lib/vz/dump/test-your-vm-restore.vma.zst"
test -s "$archive"
echo "Archive is present: $archive"