Managing HP Serviceguard A.11.20.10 for Linux, December 2012

the cluster to halt even when packages are running. This command can be issued from any running
node. Example:
cmhaltcl -f -v
This halts all the cluster nodes.
7.2.5 Automatically Restarting the Cluster
You can configure your cluster to automatically restart after an event, such as a long-term power
failure, which brought down all nodes in the cluster. This is done by setting AUTOSTART_CMCLD
to 1 in the $SGAUTOSTART file (see “Understanding the Location of Serviceguard Files” (page 129)).
7.3 Halting a Node or the Cluster while Keeping Packages Running
There may be circumstances where you want to do maintenance that involves halting a node, or
the entire cluster, without halting or failing over the affected packages. Such maintenance might
consist of anything short of rebooting the node or nodes, but a likely case is networking changes
that will disrupt the heartbeat.
New command options in Serviceguard A.11.20.00 (collectively known as Live Application Detach
(LAD)) allows you to do this kind of maintenance while keeping the packages running. The packages
are no longer monitored by Serviceguard, but the applications continue to run. Packages in this
state are called detached packages.
When you have done the necessary maintenance, you can restart the node or cluster, and normal
monitoring will resume on the packages.
NOTE: Keep in mind that the purpose of the LAD capabilities is to allow you do maintenance
on one or more nodes, or the entire cluster. If you want to do maintenance on individual packages,
or on elements of the cluster configuration that affect only one package, or a few packages, you
should probably use package maintenance mode; see “Maintaining a Package: Maintenance
Mode” (page 212).
7.3.1 What You Can Do
• Halt a node (cmhaltnode (1m) with the -d option) without causing its running packages
to halt or fail over.
Until you restart the node (cmrunnode (1m)) these packages remain detached and are not
monitored by Serviceguard.
• Halt the cluster (cmhaltcl (1m) with the -d option) without causing its running packages
to halt.
Until you restart the cluster (cmruncl (1m)) these packages remain detached and are not
being monitored by Serviceguard.
• Halt a detached package, including instances of detached multi-node packages.
• Restart normal package monitoring by restarting the node (cmrunnode) or the cluster ().
• You can forcefully halt a detached node (cmhaltnode (1m)) with the -f option.
7.3.2 Rules and Restrictions
The following rules and restrictions apply.
• All the nodes in the cluster must be running Serviceguard A.11.20.10 or later.
• All the configured cluster nodes must be reachable by an available network.
• You must be the root user (superuser) to halt or start a node or cluster with Live Application
Detach, and to halt a detached package.
7.3 Halting a Node or the Cluster while Keeping Packages Running 205