5.4. Starting, Stopping, Restarting, and Deleting Clusters
5.4. Starting, Stopping, Restarting, and Deleting Clusters You can start, stop, and restart a cluster by performing these actions on the individual nodes in the cluster. From the cluster-specific page, click on Nodes along the top of the cluster display. This displays the nodes that constitute the cluster. The start and restart operations for cluster nodes or a whole cluster allow you to create short cluster service outages if a cluster service needs to be moved to another cluster member because it running on a node that is being stopped or restarted. To stop a cluster, perform the following steps. This shuts down the cluster software in the nodes, but does not remove the cluster configuration information from the nodes and the nodes still appear in the cluster node display with a status of Not a cluster member . Select all of the nodes in the cluster by clicking on the check box to each node. Select the Leave Cluster function from the menu at the top of the page. This causes a message to appear at the top of the page indicating that each node is being stopped. Refresh the page to see the updated status of the nodes. To start a cluster, perform the following steps: Select all of the nodes in the cluster by clicking on the check box to each node. Select the Join Cluster function from the menu at the top of the page. Refresh the page to see the updated status of the nodes. To restart a running cluster, first stop all of the nodes in cluster, then start all of the nodes in the cluster, as described above. To delete a cluster entirely, perform the following steps. This causes all cluster services to stop and removes the cluster configuration information from the nodes themselves as well as removing them from the cluster display. If you later try to add an existing cluster using any of the nodes you have deleted, luci will indicate that the node is not a member of any cluster. Important Deleting a cluster is a destructive operation that cannot be undone. To restore a cluster after you have deleted it requires that you recreate and redefine the cluster from scratch. Select all of the nodes in the cluster by clicking on the check box to each node. Select the Delete function from the menu at the top of the page. If you wish to remove a cluster from the luci interface without stopping any of the cluster services or changing the cluster membership, you can use the Remove option on the Manage Clusters page, as described in Section 5.2, "Removing a Cluster from the luci Interface" .