Share Migration allows a share to be migrated from
one host#pool to another host#pool through the
"manila migrate <share> <host#pool>" command. It first
calls the driver to perform it in an optimized way if
possible. If the driver returns that it did not migrate,
it performs a generic migration.
A new field has been added to "shares" table: task_state,
which tracks migration status.
For driver migration, the method migrate_share in driver
base class should be overridden.
For generic migration, drivers may use new config options
to achieve the necessary configuration:
- migration_mounting_backend_ip: If backend has additional
exports IP for admin network, specify it here.
- migration_data_copy_node_ip: IP of entity performing
migration between backends, such as manila node or
data copy service node. This may not apply for
DHSS = true drivers.
- migration_protocol_mount_command: specify mount command
with protocol and additional parameters. Advisable to restrict
protocols per backend. Defaults to "mount -t <share_proto>".
If additional customization is needed, drivers may override
certain methods:
- _mount_share: return the mount command.
- _umount_share: return the umount command.
- _get_access_rule_for_data_copy: return an access rule with
the IP address which will allow the manila node or data copy node
to mount the share after added permission through
allow-access API command.
Change-Id: I8dde892cb7c0180b2b56d8c7d680dfe2320c2ec7
Implements: blueprint share-migration
0524ab8fc2