This article summarizes the steps required to upgrade from the wallaby release to the xena release of openstack.

Prerequisites:

• This documents expects that your cloud is deployed with a recent wallaby tag of the ntnuopenstack repository.
• You have a recent mysql backup in case things go south.
• If you want to do a rolling upgrade, the following key should be set in hiera long enough in advance that all hosts have had an puppet-run to apply it:

  • nova::upgrade_level_compute: '6.0'

  • When the upgrade is finished - set this key to 'X.X'
  • These version-numbers can be correlated to release-name in the file /usr/lib/python3/dist-packages/nova/compute/rpcapi.py

The recommended order to upgrade the services are listed below:

Keystone

This is the zero downtime approach

Before you begin

• Login to a mysql node, start the mysql CLI, and run set global log_bin_trust_function_creators=1;

Upgrade-steps (start with a single node):

1. Set apache::service_ensure: 'stopped' in hiera for the node that you are upgrading
2. Run puppet with the xena modules/tags, run apt-get dist-upgrade, and run puppet again
3. Run keystone-manage doctor and ensure nothing is wrong
4. Run keystone-manage db_sync --expand
   1. Returns nothing
5. Run keystone-manage db_sync --migrate
   1. Returns nothing
6. At this point, you may restart apache2 on this node
   1. Remove the  apache::service_ensure: 'stopped' previously set in hiera.
7. Upgrade keystone on the other nodes, one at a time
   1. Basically run step 1, 2 and 6 on the other nodes
8. When all nodes are upgraded, perform the final DB sync
   1. keystone-manage db_sync --contract

Glance

To upgrade glance without any downtime you would need to follow the following procedure:

1. Select which glance-server to upgrade first.
   1. In the node-specific hiera for this host you should set: glance::api::enabled: false 
2. Run puppet with the xena modules/tags, run apt-get dist-upgrade, and run puppet again
3. Run glance-manage db expand
4. Run glance-manage db migrate
5. Remove the glance::api::enable: false from the node-specific hiera, and run puppet again. This would re-start the glance api-server on this host.
   1. Test that this api-server works.
6. Upgrade the rest of the glance hosts (ie; step 2 for each of the remaining glance hosts)
7. Run glance-manage db contract on one of the glance-nodes.

Cinder

To upgrade cinder without any downtime, follow this procedure

1. Add the following three lines to the node-file of the first node you would like to upgrade:
   

   1. apache::service_ensure: 'stopped'

   2. cinder::scheduler::enabled: false

   3. cinder::volume::enabled: false

2. Run puppet with the xena modules/tags, run apt-get dist-upgrade, and run puppet again
3. Run cinder-manage db sync && cinder-manage db online_data_migrations
4. Remove the lines added at step 1, re-run puppet, and test that the upgraded cinder version works.
5. Perfom step 2 for the rest of the cinder nodes