Episode 21 of the InventiveHQ KVM virtualization series.
Lab verified July 2026 · Ubuntu 26.04 · libvirt 12.0.0 · QEMU 10.2.1
What this episode proves
- Map three-host quorum and every traffic path
- Define fencing authority and failure domains
- Set recovery objectives and capacity headroom
- Fail the design review when storage or fencing is single-path and undocumented
Validated workflow
1. Map three-host quorum and every traffic path
pcs quorum status
2. Define fencing authority and failure domains
pcs stonith config
3. Set recovery objectives and capacity headroom
virsh domcapabilities
4. Fail the design review when storage or fencing is single-path and undocumented
df -h /var/lib/libvirt/images
Finished state
A versioned topology, address plan, capacity model, and failure-test matrix become the HA source of truth. The public scripts contain no private keys, passwords, or tokens. Review names, addresses, paths, ownership, backups, quorum, and fencing for your own environment before running them.