Database Management

The default metadata driver for Glance uses sqlalchemy, which implies there exists a backend database which must be managed. The glance-manage binary provides a set of commands for making this easier.

The commands should be executed as a subcommand of ‘db’:

glance-manage db <cmd> <args>

Sync the Database

glance-manage db sync <version> <current_version>

Place a database under migration control and upgrade, creating it first if necessary.

Determining the Database Version

glance-manage db version

This will print the current migration level of a Glance database.

Upgrading an Existing Database

glance-manage db upgrade <VERSION>

This will take an existing database and upgrade it to the specified VERSION.

Downgrading an Existing Database

Upgrades involve complex operations and can fail. Before attempting any upgrade, you should make a full database backup of your production data. As of Kilo, database downgrades are not supported, and the only method available to get back to a prior database version is to restore from backup[1].

[1]: http://docs.openstack.org/ops-guide/ops-upgrades.html#perform-a-backup