Managing Serviceguard 11th Edition, Version A.11.16, Second Printing June 2004

Configuring Packages and Their Services
Writing the Package Control Script
Chapter 6 271
time, Pkg1 tries to cmmodpkg Pkg2. However, that cmmodpkg command
has to wait for Pkg2 startup to complete. Pkg2 tries to cmmodpkg Pkg1,
but Pkg2 has to wait for Pkg1 startup to complete, thereby causing a
command loop.
To avoid this situation, it is a good idea to always specify a
RUN_SCRIPT_TIMEOUT and a HALT_SCRIPT_TIMEOUT for all packages,
especially packages that use Serviceguard commands in their control
scripts. If a timeout is not specified and your configuration has a
command loop as described above, inconsistent results can occur,
including a hung cluster.
Support for Additional Products
The package control script template provides exits for use with
additional products, including MetroCluster with Continuous Access/CA,
MetroCluster with EMC SRDF, and the HA NFS toolkit. Refer to the
additional product’s documentation for details about how to create a
package using the hooks that are provided in the control script.