Red Hat ENTERPRISE LINUX 5 - ADMINISTRATION Manual page 59

cluster service operation. To manage the cluster system further, choose the Cluster
Configuration tab.)
3. Clicking Create New Configuration causes the New Configuration dialog box to be displayed
Figure 5.2, "Creating A New
(refer to
a text box for cluster name and the following checkboxes: Custom Configure Multicast and Use
a Quorum Disk. In most circumstances you only need to configure the cluster name.
Note
Choose the cluster name carefully. The only way to change the name of a Red Hat
cluster is to create a new cluster configuration with the new name.
Custom Configure Multicast
Red Hat Cluster software chooses a multicast address for cluster management communication
among cluster nodes. If you need to use a specific multicast address, click the Custom Configure
Multicast checkbox and enter a multicast address in the Address text boxes.
Note
IPV6 is not supported for Cluster Suite in Red Hat Enterprise Linux 5.
If you do not specify a multicast address, the Red Hat Cluster software (specifically, cman, the
Cluster Manager) creates one. It forms the upper 16 bits of the multicast address with 239.192 and
forms the lower 16 bits based on the cluster ID.
Note
The cluster ID is a unique identifier that cman generates for each cluster. To view the
cluster ID, run the cman_tool status command on a cluster node.
If you do specify a multicast address, you should use the 239.192.x.x series that cman uses.
Otherwise, using a multicast address outside that range may cause unpredictable results. For
example, using 224.0.0.x (which is "All hosts on the network") may not be routed correctly, or even
routed at all by some hardware.
Note
If you specify a multicast address, make sure that you check the configuration of
routers that cluster packets pass through. Some routers may take a long time to learn
addresses, seriously impacting cluster performance.
Configuration"). The New Configuration dialog box provides
Custom Configure Multicast
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