Red Hat ENTERPRISE LINUX 4 - ADMINISTRATION Manual

Also see for ENTERPRISE LINUX 4 - DEVELOPER TOOLS GUIDE: Installation guide Installation guide Tuning guide Installation guide Manual

Contents

Chapter 6. Managing Red Hat Cluster With system-config-cluster80ImportantIf you are changing the number of cluster members, refer to Section 5.5, “Adding andDeleting Members”. You must take into account certain circumstances for both DLM andGULM clusters when adding or deleting members.To edit the cluster configuration file, click the Cluster Configuration tab in the cluster configurationGUI. Clicking the Cluster Configuration tab displays a graphical representation of the clusterconfiguration. Change the configuration file according the the following steps:1. Make changes to cluster elements (for example, create a service).2. Propagate the updated configuration file throughout the cluster by clicking Send to Cluster.NoteThe Cluster Configuration Tool does not display the Send to Cluster button ifthe cluster is new and has not been started yet, or if the node from which you arerunning the Cluster Configuration Tool is not a member of the cluster. If the Sendto Cluster button is not displayed, you can still use the Cluster Configuration Tool;however, you cannot propagate the configuration. You can still save the configurationfile. For information about using the Cluster Configuration Tool for a new clusterconfiguration, refer to Chapter 5, Configuring Red Hat Cluster With system-config-cluster.3. Clicking Send to Cluster causes a Warning dialog box to be displayed. Click Yes to save andpropagate the configuration.4. Clicking Yes causes an Information dialog box to be displayed, confirming that the currentconfiguration has been propagated to the cluster. Click OK.5. Click the Cluster Management tab and verify that the changes have been propagated to thecluster members.6.4. Backing Up and Restoring the Cluster DatabaseThe Cluster Configuration Tool automatically retains backup copies of the three most recently usedconfiguration files (besides the currently used configuration file). Retaining the backup copies is usefulif the cluster does not function correctly because of misconfiguration and you need to return to aprevious working configuration.Each time you save a configuration file, the Cluster Configuration Tool saves backup copiesof the three most recently used configuration files as /etc/cluster/cluster.conf.bak.1,/etc/cluster/cluster.conf.bak.2, and /etc/cluster/cluster.conf.bak.3. Thebackup file /etc/cluster/cluster.conf.bak.1 is the newest backup, /etc/cluster/cluster.conf.bak.2 is the second newest backup, and /etc/cluster/cluster.conf.bak.3is the third newest backup.If a cluster member becomes inoperable because of misconfiguration, restore the configuration fileaccording to the following steps: