Managing HP Serviceguard for Linux Ninth Edition, April 2009

a new template, and then copy the parameter values into it. In the new template, read
the descriptions and defaults of the choices that did not exist when the original
configuration was made. For example, the default for failover_policy is now
configured_node and the default for failback_policy is now manual.
For full details of the current parameters and their default values, see Chapter 6:
“Configuring Packages and Their Services ” (page 189), and the package configuration
file template itself.
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 300 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 nodes, or that the package has a dependency that is not being met. When a
package has failed on one node and is enabled to switch to another node, it will start
up automatically in a new location where its dependencies are met. This process is
known as package switching, or remote switching.
How Packages Run 61