Alibaba Cloud Elasticsearch allows you to perform the following operations to make changes to a cluster: restart the cluster or a node in the cluster, upgrade or downgrade the configuration of the cluster, upgrade the version of the cluster, and migrate nodes in the cluster across zones. If the cluster is a multi-zone cluster, you can also perform a switchover on faulty nodes in the cluster. After you perform the preceding operations, you can view the progress of the operations in the Elasticsearch console. This topic describes the scenarios in which you can perform the preceding operations.
|Restart a cluster or node||If your cluster is in an abnormal state, you can restart or forcibly restart the cluster based on its health status. For more information, see Restart a cluster or node.|
|Upgrade or downgrade the configuration of a cluster||
|Upgrade the version of a cluster||You can perform an in-place upgrade for your cluster version or kernel. In-place upgrades do not affect your business. Only some versions support in-place upgrades. For more information, see Upgrade the version of a cluster.|
|Perform a switchover on faulty nodes in a cluster||Multi-zone clusters offer enhanced disaster recovery capabilities. If your cluster is a multi-zone cluster and the nodes in one zone become faulty, the nodes in the remaining zones can still provide services without interruption. In addition, you can perform a switchover on the faulty nodes in the Elasticsearch console to isolate the faulty nodes. Then, the system adds computing resources to the remaining zones to make up for the resource loss that is caused by the faulty nodes. For more information, see Deploy and use a multi-zone Elasticsearch cluster.|
|Migrate nodes across zones||If you want to upgrade the configuration of your cluster but the zone where the cluster resides does not provide sufficient resources for the upgrade, you can first migrate nodes in the cluster to a different zone. For more information, see Migrate nodes in a zone.|
|View the progress of a cluster task||After you perform an operation to make a change to your cluster, you can click the Tasks icon on the Basic Information page of the cluster in the Elasticsearch console to view the progress of the operation. In the Tasks dialog box, you can view the progress of a running task, such as a cluster creation task, cluster restart task, or data migration task. For more information, see View the progress of a cluster task.|