6.3. Modifying the Cluster Configuration
To modify the cluster configuration (the cluster configuration file (
/etc/cluster/cluster.conf), use the Cluster Configuration Tool. For more information about using the Cluster Configuration Tool, refer to Chapter 5, Configuring Red Hat Cluster With system-config-cluster.
Warning
Do not manually edit the contents of the
/etc/cluster/cluster.conf file without guidance from an authorized Red Hat representative or unless you fully understand the consequences of editing the /etc/cluster/cluster.conf file manually.
Important
Although the Cluster Configuration Tool provides a parameter in the Properties dialog box of each cluster member, that parameter is intended only for use during initial cluster configuration. Furthermore, it is recommended that you retain the default value of
1. For more information about using the Cluster Configuration Tool, refer to Chapter 5, Configuring Red Hat Cluster With system-config-cluster.
Important
If you are changing the number of cluster members, refer to Section 5.5, “Adding and Deleting Members”. You must take into account certain circumstances for both DLM and GULM clusters when adding or deleting members.
To edit the cluster configuration file, click the tab in the cluster configuration GUI. Clicking the tab displays a graphical representation of the cluster configuration. Change the configuration file according the the following steps:
- Make changes to cluster elements (for example, create a service).
- Propagate the updated configuration file throughout the cluster by clicking .
Note
The Cluster Configuration Tool does not display the button if the cluster is new and has not been started yet, or if the node from which you are running the Cluster Configuration Tool is not a member of the cluster. If the button is not displayed, you can still use the Cluster Configuration Tool; however, you cannot propagate the configuration. You can still save the configuration file. For information about using the Cluster Configuration Tool for a new cluster configuration, refer to Chapter 5, Configuring Red Hat Cluster Withsystem-config-cluster. - Clicking causes a Warning dialog box to be displayed. Click to save and propagate the configuration.
- Clicking causes an Information dialog box to be displayed, confirming that the current configuration has been propagated to the cluster. Click .
- Click the tab and verify that the changes have been propagated to the cluster members.
