Managing HP Serviceguard for Linux, Eighth Edition, March 2008

Understanding Serviceguard Software Components
How Packages Run
Chapter 3 61
How Packages Run
Packages are the means by which Serviceguard starts and halts
configured applications. Failover packages are also units of failover
behavior in Serviceguard. A package is a collection of services, disk
volumes and IP addresses that are managed by Serviceguard to ensure
they are available. There can be a maximum of 150 packages per cluster
and a total of 900 services per cluster.
What Makes a Package Run?
There are 3 types of packages:
• The failover package is the most common type of package. It runs on
one node at a time. If a failure occurs, it can switch to another node
listed in its configuration file. If switching is enabled for several
nodes, the package manager will use the failover policy to determine
where to start the package.
• A system multi-node package runs on all the active cluster nodes at
the same time. It can be started or halted on all nodes, but not on
individual nodes.
• A multi-node package can run on several nodes at the same time. If
auto_run is set to yes, Serviceguard starts the multi-node package
on all the nodes listed in its configuration file. It can be started or
halted on all nodes, or on individual nodes, either by user command
(cmhaltpkg) or automatically by Serviceguard in response to a
failure of a package component, such as service or subnet.
System multi-node packages are supported only for use by applications
supplied by Hewlett-Packard.
A failover package can be configured to have a dependency on a
multi-node or system multi-node package. The package manager cannot
start a package on a node unless the package it depends on is already up
and running on that node.
The package manager will always try to keep a failover package running
unless there is something preventing it from running on any node. The
most common reasons for a failover package not being able to run are
that auto_run is disabled so Serviceguard is not allowed to start the
package, that node switching is disabled for the package on particular