The docs at https://jujucharms.com/docs/stable/developer-debugging say that
To debug actions, you use the same command, like this: juju debug-hooks <service/unit> [action-name action-name2 …] but if I try $ juju debug-hooks keystone/11 resume ERROR unit "keystone/11" does not contain hook “resume” while instead: $ juju list-actions keystone Action Description git-reinstall Reinstall keystone from the openstack-origin-git repositories. openstack-upgrade Perform openstack upgrades. Config option action-managed-upgrade must be set to True. pause Pause keystone services. If the keystone deployment is clustered using the hacluster charm, the corresponding hacluster unit on the node must first be paused as well. Not doing so may lead to an interruption of service. resume Resume keystone services. If the keystone deployment is clustered using the hacluster charm, the corresponding hacluster unit on the node must be resumed as well. This is: $ juju version 2.2.4-xenial-amd64 — Beppe -- Juju mailing list Juju@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/juju