On Thu, Mar 12, 2026 at 00:51:54 -0000, roy-orbitson--- via Devel wrote:
When libvirt components get updated on a hypervisor, VMs continue running with obsolete files. Programs like "needrestart" alert one to this condition with messages like:
VM guests are running outdated hypervisor (qemu) binaries on this host: 'bazquux' with pid 1234
Normal restarting of a VM (from within or with `virsh reboot ...`) does not resolve it because it's 'warm'; VMs must be completely shut down then started again to utilise the updates. Afaik, to do so reliably, in a way that minimises downtime, requires scripts like this:
(d=bazquux; virsh shutdown --domain "$d" && until LC_ALL=C LANG=C virsh domstate --domain "$d" | grep -Fi 'shut off' &> /dev/null; do echo ...; sleep 1; done && virsh start --domain "$d")
Adding a timeout complicates that further. Options for this logic to be performed by virsh would be beneficial, as a single operation:
virsh reboot --domain bazquux --cold
And by allowing poweroff to wait:
(d=bazquux; virsh shutdown --domain "$d" --synchronous && virsh start --domain "$d")
Aside from the complexities Michal pointed out, I've added 'virsh await' some time ago. It allows you to wait for VM to reach a "condition", one of the conditions I've added would allow you to do what you want: virsh shutdown $DOM; virsh await --condition domain-inactive $DOM 'virsh await' terminates only after $DOM is in inactive state. It also supports '--timeout' to break out from deadlocks if needed.