Managing HP Serviceguard A.11.20.00 for Linux, June 2012

• You cannot detach package that is in maintenance mode, and you cannot place a package
into maintenance mode if any of its dependent packages are detached. Also, you cannot put
a detached package in maintenance mode.
For more information about maintenance mode, see“Maintaining a Package: Maintenance
Mode” (page 197). For more information about dependencies, see “About Package
Dependencies” (page 100).
• You cannot make configuration changes to a package or a cluster in which any packages
are detached.
cmapplyconf (1m) will fail.
• You cannot halt detached packages while the cluster is down.
If you have halted a node and detached its packages, you can log in as superuser on any
other node still running in the cluster and halt any of the detached packages. But if you have
halted the cluster, you must restart it, re-attaching the packages, before you can halt any of
the packages.
• cmeval (1m) does not support Live Application Detach.
See “Previewing the Effect of Cluster Changes” (page 202) for more information about cmeval.
• In preview mode (-t) cmrunnode and cmruncl can provide only a partial assessment of
the effect of re-attaching packages.
The assessment may not accurately predict the placement of packages that depend on the
packages that will be re-attached. For more information about preview mode, see “Previewing
the Effect of Cluster Changes” (page 202).
• cmmodpkg -e -t is not supported for a detached package.
• You cannot run a package that has been detached.
This could come up if you detect that a package has failed while detached (and hence not
being monitored by Serviceguard). Before you could restart the package on another node,
you would need to run cmhaltpkg (1m) to halt the package on the node where it is
detached.
• You cannot halt a package that is in a transitory state such as STARTING or HALTING.
For more information about package states, see “Package Status and State” (page 181).
Additional Points To Note
Keep the following points in mind:
• When packages are detached, they continue to run, but without high availability protection.
Serviceguard does not detect failures of components of detached packages, and packages
are not failed over.
IMPORTANT: This means that you will need to detect any errors that occur while the package
is detached, and take corrective action by running cmhaltpkg to halt the detached package
and cmrunpkg (1m) to restart the package on another node.
• When you restart a node or cluster whose packages have been detached, the packages are
re-attached; that is, Serviceguard begins monitoring them again.
At this point, Serviceguard checks the health of the packages that were detached and takes
any necessary corrective action — for example, if a failover package has in fact failed while
it was detached, Serviceguard will halt it and restart it on another eligible node.
Halting a Node or the Cluster while Keeping Packages Running 193