Installation guide

5. Save /etc/cl uster/cl uster.co nf.
6. (O pti o nal ) Validate the updated file against the cluster schema (cluster. rng ) by
running the ccs_co nfi g _val i d ate command. For example:
[root@ example-01 ~]# ccs_co nfi g _val i d ate
Configuration validates
7. Run the cman_too l versi o n -r command to propagate the configuration to the rest of the
cluster nodes. This will also run additional validation. It is necessary that ri cci be running
in each cluster node to be able to propagate updated cluster configuration information.
8. Verify that the updated configuration file has been propagated.
9. Proceed to Section 7.4, “Configuring Failover Domains” .
If required, you can configure complex configurations with multiple fence methods per node and with
multiple fence devices per fence method. When specifying multiple fence methods per node, if fencing
fails using the first method, fenced , the fence daemon, tries the next method, and continues to cycle
through methods until one succeeds.
Sometimes, fencing a node requires disabling two I/O paths or two power ports. This is done by
specifying two or more devices within a fence method. fenced runs the fence agent once for each
fence-device line; all must succeed for fencing to be considered successful.
More complex configurations are shown in the section called “ Fencing Configuration Examples” .
You can find more information about configuring specific fence devices from a fence-device agent
man page (for example, the man page for fence_apc). In addition, you can get more information
about fencing parameters from Appendix A, Fence Device Parameters, the fence agents in
/usr/sbi n/, the cluster schema at /usr/share/cl uster/cluster. rng , and the annotated
schema at /usr/share/d o c/cman-X. Y . ZZ/cluster_co nf. html (for example,
/usr/share/d o c/cman-3. 0 . 12/cluster_conf. html ).
Note
As of Red Hat Enterprise Linux Release 6.4, you can test the fence configuration for each node
in a cluster with the fence_check utility. For information on this utility, see the
fence_check(8) man page.
Fencing Configuration Examples
The following examples show a simple configuration with one fence method per node and one fence
device per fence method:
Example 7.3, “ APC Fence Device Added to cl uster. co nf ”
Example 7.4, “Fence Methods Added to cl uster. co nf ”
The following examples show more complex configurations:
Example 7.5, “ cl uster. co nf: Multiple Fence Methods per Node”
Example 7.6, “ cl uster. co nf: Fencing, Multipath Multiple Ports”
Red Hat Ent erprise Linux 6 Clust er Administ rat ion
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