Installation guide

2. (O pti o nal ) If you are configuring a two-node cluster, you can add the following line to the
configuration file to allow a single node to maintain quorum (for example, if one node fails):
<cman two _no d e= "1"
expected_vo tes= "1"/>
When you add or remove the two _no d e option from the cl uster. co nf file, you must restart
the cluster for this change to take effect when you update the configuration. For information
on updating a cluster configuration, refer to Section 8.4, “Updating a Configuration” . For an
example of specifying the two _no d e option, refer to Example 7.2, “ cl uster. co nf Sample:
Basic Two-Node Configuration” .
3. Specify the cluster name and the configuration version number using the cl uster attributes:
name and co nfi g _versi o n (refer to Example 7.1, “cl uster. co nf Sample: Basic
Configuration” or Example 7.2, “ cl uster. co nf Sample: Basic Two-Node Configuration” ).
4. In the cl usterno d es section, specify the node name and the node ID of each node using
the cl usternod e attributes: name and no d ei d . The node name can be up to 255 bytes in
length.
5. Save /etc/cl uster/cl uster.co nf.
6. Validate the 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. Propagate the configuration file to /etc/cl uster/ in each cluster node. For example, you
could propagate the file to other cluster nodes using the scp command.
Note
Propagating the cluster configuration file this way is necessary the first time a cluster is
created. Once a cluster is installed and running, the cluster configuration file can be
propagated using the cman_to o l versi o n -r command. It is possible to use the
scp command to propagate an updated configuration file; however, the cluster
software must be stopped on all nodes while using the scp command.In addition, you
should run the ccs_co nfi g _val i d ate if you propagate an updated configuration
file via the scp.
Note
While there are other elements and attributes present in the sample configuration file
(for example, fence and fenced evi ces), there is no need to populate them now.
Subsequent procedures in this chapter provide information about specifying other
elements and attributes.
8. Start the cluster. At each cluster node run the following command:
service cman start
For example:
Red Hat Ent erprise Linux 6 Clust er Administ rat ion
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