Using Serviceguard Commands to Add Previously Configured Nodes to a Running Cluster

Use the cmrunnode command to join one or more nodes to an already running cluster. Any node you add must already be a part of the cluster configuration. The following example adds node ftsys8 to the cluster that was just started with only nodes ftsys9 and ftsys10. The-v(verbose) option prints out all the messages:

cmrunnode -v ftsys8

By default, cmrunnode will do network validation, making sure the actual network setup matches the configured network setup. This is the recommended method. If you have recently checked the network and find the check takes a very long time, you can use the -w none option to bypass the validation.

Since the node’s cluster is already running, the node joins the cluster. Packages may be started, depending on the package configuration; see node_name” (page 235)). If the node does not find its cluster running, or the node is not part of the cluster configuration, the command fails.

Removing Nodes from Participation in a Running Cluster

You can use Serviceguard Manager, or Serviceguard commands as shown below, to remove nodes from active participation in a cluster. This operation halts the cluster daemon, but it does not modify the cluster configuration. To remove a node from the cluster configuration permanently, you must recreate the cluster configuration file. See the next section.

Halting a node is a convenient way of bringing it down for system maintenance while keeping its packages available on other nodes. After maintenance, the package can be returned to its primary node. See “Moving a Failover Package ” (page 286).

To return a node to the cluster, use cmrunnode.

NOTE: HP recommends that you remove a node from participation in the cluster (by running cmhaltnode as shown below, or Halt Node in Serviceguard Manager) before running the HP-UX shutdown command, especially in cases in which a packaged application might have trouble during shutdown and not halt cleanly.

Use cmhaltnode to halt one or more nodes in a cluster. The cluster daemon on the specified node stops, and the node is removed from active participation in the cluster.

To halt a node with a running package, use the -foption. If a package was running that can be switched to an adoptive node, the switch takes place and the package starts on the adoptive node. For example, the following command causes the Serviceguard daemon running on node ftsys9 in the sample configuration to halt and the package running on ftsys9 to move to an adoptive node The -v(verbose) option prints out messages:

cmhaltnode -f -v ftsys9

This halts any packages running on the node ftsys9 by executing the halt instructions in each package's master control script. ftsys9 is halted and the packages start on their adoptive node.

Halting the Entire Cluster

You can use Serviceguard Manager, or Serviceguard commands as shown below, to halt a running cluster.

Use cmhaltcl to halt the entire cluster. This command causes all nodes in a configured cluster to halt their Serviceguard daemons. You can use the -foption to force the cluster to halt even when packages are running. You can use the command on any running node, for example:

cmhaltcl -f -v

This halts all the cluster nodes.

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HP Serviceguard Removing Nodes from Participation in a Running Cluster, Halting the Entire Cluster, Cmrunnode -v ftsys8