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9.4. Updating a Configuration
Updating the cluster configuration consists of editing the cluster configuration file (
/etc/cluster/cluster.conf) and propagating it to each node in the cluster. You can update the configuration using either of the following procedures:
9.4.1. Updating a Configuration Using cman_tool version -r
To update the configuration using the
cman_tool version -r command, perform the following steps:
- At any node in the cluster, edit the
/etc/cluster/cluster.conffile. - Update the
config_versionattribute by incrementing its value (for example, changing fromconfig_version="2"toconfig_version="3"). - Save
/etc/cluster/cluster.conf. - Run the
cman_tool version -rcommand to propagate the configuration to the rest of the cluster nodes. It is necessary thatriccibe running in each cluster node to be able to propagate updated cluster configuration information. - Verify that the updated
cluster.confconfiguration file has been propagated. If not, use thescpcommand to propagate it to/etc/cluster/in each cluster node. - You may skip this step (restarting cluster software) if you have made only the following configuration changes:
- Deleting a node from the cluster configuration—except where the node count changes from greater than two nodes to two nodes. For information about deleting a node from a cluster and transitioning from greater than two nodes to two nodes, refer to 節 9.2, “Deleting or Adding a Node”.
- Adding a node to the cluster configuration—except where the node count changes from two nodes to greater than two nodes. For information about adding a node to a cluster and transitioning from two nodes to greater than two nodes, refer to 節 9.2.2, “Adding a Node to a Cluster”.
- Changes to how daemons log information.
- HA service/VM maintenance (adding, editing, or deleting).
- Resource maintenance (adding, editing, or deleting).
- Failover domain maintenance (adding, editing, or deleting).
Otherwise, you must restart the cluster software as follows:- At each node, stop the cluster software according to 節 9.1.2, “Stopping Cluster Software”.
- At each node, start the cluster software according to 節 9.1.1, “Starting Cluster Software”.
Stopping and starting the cluster software ensures that any configuration changes that are checked only at startup time are included in the running configuration. - At any cluster node, run
cman_tool nodesto verify that the nodes are functioning as members in the cluster (signified as "M" in the status column, "Sts"). For example:[root@example-01 ~]#
cman_tool nodesNode Sts Inc Joined Name 1 M 548 2010-09-28 10:52:21 node-01.example.com 2 M 548 2010-09-28 10:52:21 node-02.example.com 3 M 544 2010-09-28 10:52:21 node-03.example.com - At any node, using the
clustatutility, verify that the HA services are running as expected. In addition,clustatdisplays status of the cluster nodes. For example:[root@example-01 ~]#
clustatCluster Status for mycluster @ Wed Nov 17 05:40:00 2010 Member Status: Quorate Member Name ID Status ------ ---- ---- ------ node-03.example.com 3 Online, rgmanager node-02.example.com 2 Online, rgmanager node-01.example.com 1 Online, Local, rgmanager Service Name Owner (Last) State ------- ---- ----- ------ ----- service:example_apache node-01.example.com started service:example_apache2 (none) disabled - If the cluster is running as expected, you are done updating the configuration.