vitrage/doc/source/contributor/nova-config.rst

Nova Datasource Configuration

By default, Nova datasource listens to Nova versioned notifications. If you are using Nova legacy notifications, then it should be indicated in Vitrage configuration as well.

That is, if you have in /etc/nova/nova.conf or in /etc/nova/nova-cpu.conf:

notification_format = unversioned

Then you should set in /etc/vitrage/vitrage.conf:

[DEFAULT]
use_nova_versioned_notifications = False

In other cases there is no need to set this option.