Managing HP Serviceguard for Linux, Eighth Edition, March 2008

Planning and Documenting an HA Cluster
Package Configuration Planning
Chapter 4 123
About Package Dependencies
A package can have dependencies on other packages, meaning the
package will not start on a node unless the packages it depends on are
running on that node.
You can make a package dependent on any other package or packages
running on the same cluster node, subject to the restrictions spelled out
in Chapter 6, under dependency_condition (see page 216).
Make a package dependent on another package if the first package
cannot (or should not) function without the services provided by the
second. For example, pkg1 might run a real-time web interface to a
database managed by pkg2. In this case it might make sense to make
pkg1 dependent on pkg2.
In considering whether or not to create a dependency between packages,
consider the Rules and Guidelines that follow.
All packages switch
following a system reboot
on the node when a
specific service fails. Halt
scripts are not run.
• service_fail_fast_enabled set to
yes for a specific service.
• auto_run set to yes for all packages.
All packages switch
following a system reboot
on the node when any
service fails.
• service_fail_fast_enabled set to
yes for all services.
• auto_run set to yes for all packages.
Table 4-1 Package Failover Behavior (Continued)
Switching Behavior Parameters in Configuration File