Managing Serviceguard 12th Edition, March 2006

Understanding Serviceguard Software Components
How the Package Manager Works
Chapter 3 83
On Combining Failover and Failback Policies Combining a
FAILOVER_POLICY of MIN_PACKAGE_NODE with a FAILBACK_POLICY of
AUTOMATIC can result in a package’s running on a node where you did not
expect it to run, since the node running the fewest packages will
probably not be the same host every time a failover occurs.
Using Older Package Configuration Files
If you are using package configuration files that were generated using a
previous version of Serviceguard, we recommend you use the cmmakepkg
command to open 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.
In Serviceguard A.11.17 and later, you specify a package type parameter;
the PACKAGE_TYPE for a traditional package is the default value,
FAILOVER.
Starting with the A.11.12 version of Serviceguard, the
PKG_SWITCHING_ENABLED parameter was renamed AUTO_RUN. The
NET_SWITCHING_ENABLED parameter was renamed to
LOCAL_LAN_FAILOVER_ALLOWED.
Using the Event Monitoring Service
Basic package resources include cluster nodes, LAN interfaces, and
services, which are the individual processes within an application. All of
these are monitored by Serviceguard directly. In addition, you can use
the Event Monitoring Service registry through which add-on monitors
can be configured. This registry allows other software components to
supply monitoring of their resources for Serviceguard. Monitors
currently supplied with other software products include EMS (Event
Monitoring Service) High Availability Monitors, and an ATM monitor.
If a registered resource is configured in a package, the package manager
calls the resource registrar to launch an external monitor for the
resource. Resources can be configured to start up either at the time the
node enters the cluster or at the end of package startup. The monitor
then sends messages back to Serviceguard, which checks to see whether