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Chapter 7. Managing Red Hat High Availability Add-On With ccs

This chapter describes various administrative tasks for managing the Red Hat High Availability Add-On by means of the ccs command, which is supported as of the Red Hat Enterprise Linux 6.1 release and later. This chapter consists of the following sections:

7.1. Managing Cluster Nodes

This section documents how to perform the following node-management functions with the ccs command:

7.1.1. Causing a Node to Leave or Join a Cluster

You can use the ccs command to cause a node to leave a cluster by stopping cluster services on that node. Causing a node to leave a cluster does not remove the cluster configuration information from that node. Making a node leave a cluster prevents the node from automatically joining the cluster when it is rebooted.
To cause a node to leave a cluster, execute the following command, which stops cluster services on the node specified with the -h option:
ccs -h host --stop
When you stop cluster services on a node, any service that is running on that node will fail over.
To delete a node entirely from the cluster configuration, use the --rmnode option of the ccs command, as described in Section 6.4, “Creating and Modifying a Cluster”.
To cause a node to rejoin a cluster execute the following command, which starts cluster services on the node specified with the -h option:
ccs -h host --start

7.1.2. Adding a Member to a Running Cluster

To add a member to a running cluster, add a node to the cluster as described in Section 6.4, “Creating and Modifying a Cluster”. After updating the configuration file, propagate the file to all nodes in the cluster and be sure to activate the new cluster configuration file, as described in Section 6.15, “Propagating the Configuration File to the Cluster Nodes”.

Note

When you add a node to a cluster that uses UDPU transport, you must restart all nodes in the cluster for the change to take effect.