If you will be performing a rolling upgrade of your compute hosts you will need to set explicit API version limits to ensure compatibility between your Juno and Kilo environments.
Before starting Kilo controller or compute services, we need to set
the compute option in the upgrade_levels section of nova.conf to
juno:
crudini --set /etc/nova/nova.conf upgrade_levels compute juno
You will need to make this change on your controllers and on your compute hosts.
You will undo this operation after upgrading all of your compute hosts to OpenStack Kilo.
After you have upgraded all of your hosts to Kilo, you will want to remove the API limits configured in the previous step. On all of your hosts:
crudini --del /etc/nova/nova.conf upgrade_levels compute
After making the configuration change, you will need to restart your Nova services. On your compute hosts, run:
openstack-service restart nova
And then restart Nova services on your controllers. In a non-HA environment, you can simply run the following on all of your controllers:
openstack-service restart nova
In a Pacemaker controlled HA environment, you will need to first
unmanage the Nova resources by running pcs resource unmanage on one
of your controllers:
pcs resource unmanage openstack-nova-novncproxy-clone
pcs resource unmanage openstack-nova-consoleauth-clone
pcs resource unmanage openstack-nova-conductor-clone
pcs resource unmanage openstack-nova-api-clone
pcs resource unmanage openstack-nova-scheduler-clone
Restart the services on all controllers:
openstack-service restart nova
And then return control to Pacemaker:
pcs resource manage openstack-nova-scheduler-clone
pcs resource manage openstack-nova-api-clone
pcs resource manage openstack-nova-conductor-clone
pcs resource manage openstack-nova-consoleauth-clone
pcs resource manage openstack-nova-novncproxy-clone