trove/doc/source/user/upgrade-cluster-datastore.rst

Upgrade cluster datastore

Caution

Database clustering function is still in experimental, should not be used in production environment.

Upgrading datastore for cluster instances is very similar to upgrading a single instance.

Trove tries to perform a rolling upgrade so that there won't be any downtime. However, it is not always possible and, for example, in case of Redis upgrade, some of its slots may be temporarily unavailable.

Trove strategy upgrades every instance in the entire cluster one by one. Upgrading is finished once all instances are upgraded.

Please check the guide for datastore upgrade to check prerequisistes.

This example shows you how to upgrade Redis datastore (version 3.2.6) for a cluster.

Upgrading cluster

1. Check cluster task

   Use openstack database cluster list to check whether the task of your cluster is NONE.

   $ openstack database cluster list
   +--------------------------------------+---------------+-----------+-------------------+-----------+
   | ID                                   | Name          | Datastore | Datastore Version | Task Name |
   +--------------------------------------+---------------+-----------+-------------------+-----------+
   | 05f2e7b7-8dac-453f-ad5d-38195cd5718f | redis_cluster | redis     | 3.2.6             | NONE      |
   +--------------------------------------+---------------+-----------+-------------------+-----------+

2. Check if target version is available

   Use openstack datastore version list to list all available versions your datastore.

   $ openstack datastore version list redis
   +--------------------------------------+-------+
   | ID                                   | Name  |
   +--------------------------------------+-------+
   | 483debec-b7c3-4167-ab1d-1765795ed7eb | 3.2.6 |
   | 507f666e-193c-4194-9d9d-da8342dcb4f1 | 3.2.7 |
   +--------------------------------------+-------+

3. Run cluster-upgrade

   Use openstack database cluster upgrade command to upgrade your datastore for the selected instance.

   $ openstack database cluster upgrade 05f2e7b7-8dac-453f-ad5d-38195cd5718f 3.2.7

4. Wait until task changes from UPGRADING_CLUSTER to NONE

   You can use openstack database cluster list to check the current task.

   $ openstack database cluster list
   +--------------------------------------+---------------+-----------+-------------------+-----------+
   | ID                                   | Name          | Datastore | Datastore Version | Task Name |
   +--------------------------------------+---------------+-----------+-------------------+-----------+
   | 05f2e7b7-8dac-453f-ad5d-38195cd5718f | redis_cluster | redis     | 3.2.7             | NONE      |
   +--------------------------------------+---------------+-----------+-------------------+-----------+

Other clusters

Upgrade for other clusters works in the same way. Currently Trove supports upgrades for the following cluster datastores:

• MySQL.
• MariaDB.
• Redis.