Maintenance in Managed Service for OpenSearch
Maintenance means:
- Automatic installation of OpenSearch updates and revisions for node groups (including disabled clusters).
- Changes to the node class and storage size.
- Other maintenance activities.
Major DBMS version is not changed during maintenance.
In Managed Service for OpenSearch single-node clusters, a single node undergoes maintenance. This means, if a cluster needs to be restarted during maintenance, it will become unavailable.
In multi-node clusters, nodes undergo maintenance one by one. The nodes are queued randomly. If a node needs to be restarted during maintenance, it becomes unavailable while being restarted. If you access a cluster using the FQDN of the OpenSearch node, the cluster may become unavailable. To make your application continuously available, access the cluster using a special FQDN always pointing to the available node.