Running the cluster

This is about daily operations. Creating VM instances is covered in kiss-configure.

Overview

Run kiss-overview:

OK: kissclusterd.service is running
OK: Active target: primary-vms.target

VM status:
vm@vm1.service   loaded active running VM vm1
vm@vm2.service   loaded active running VM vm2

DRBD status:
 0:vm1/0      Connected Primary/Secondary UpToDate/UpToDate 
 4:vm2/0      Connected Primary/Secondary UpToDate/UpToDate 
 5:vm2/1      Connected Primary/Secondary UpToDate/UpToDate 

This shows the status of kissclusterd (which should be running, obviously), all defined VMs (that should be running if this is their primary host), and the status of the DRBD resources.

Starting/stopping VMs

VMs can be started and stopped via systemctl, as vm@NAME.service. Stopping uses kiss-vm-monitor NAME powerdown, so it sends an ACPI shutdown signal and waits for the VM to cleanly shut down.

Migrating VMs

VMs can be live-migrated via kiss-migrate. This tries to catch any errors, but be careful. kiss-migrate --all can be used to migrate all running VMs to the other node, e.g. if you want to shutdown one node.

Taking a node offline, or rebooting it

If you just reboot or powerdown a node without migrating the VMs, they will be shut down. Then, the other node's kissclusterd will eventually see this node is down and start them again. This should bring an outage of about a minute.

To have a smooth reboot/powerdown, migrate them as shown above. When the node comes up again, it will automatically start kissclusterd, both nodes will soon try to switch to primary-vms.target, but the other node will not shut down any VMs due to this, so this node will not be able to start them.

Thus, you have to migrate them over (one by one) manually.