Excerpts from Henry Nash's message of 2016-09-15 00:29:44 +0100: > Jay, > > I agree with your distinction - and when I am referring to rolling upgrades > for keystone I am referring to when you are running a cluster of keystones > (for performance and/or redundancy), and you want to roll the upgrade across > the cluster without creating downtime of the overall keystone service. Such a > keystone cluster deployment will be common in large clouds - and prior to > Newton, keystone did not support such a rolling upgrade (you had to take all > the nodes down, upgrade the DB and then boot them all back up). In order to > support such a rolling upgrade you either need to have code that can work on > different DB versions (either explicitly or via versioned objects), or you > hide the schema changes by “data synchronisation via Triggers”, which is > where this whole thread came from. >
It doesn't always need to be explicit or through versioned objects. One can often manipulate the schema and even migrate data without disturbing old code. __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
