If the shutdown node:
- Try to migrate to other hosts
- If it was not possible to migrate to another host, then execute virch save DOMAIN FileName.save
This necessity is due to the fact that the cluster is used only from 3 nodes. However, they are all in the same rack. In the event of a power outage, the UPS will give the OS command to shut down (you can configure your own additional script).
As a result, no VM will be able to migrate anywhere.
In this case, it is necessary to save the state, and not to complete the work (not everyone supports ACPI), an analogue of the [virsh save] command. So that when the node is turned on, this VM is loaded from the saved state.
Versions of the related components and OS (frontend, hypervisors, VMs): OpenNebula 18.104.22.168, QEMU/KVM, Win/Linux
Thanks in advance to anyone who can help with advice.