Managing HP Serviceguard A.12.00.00 for Linux, June 2014

• An NFS file system should not be mounted on more than one mount point at the same time.
• Access to an NFS file system used by a package should be restricted to the nodes that can
run the package.
For more information, see the white paper Using NFS as a file system type with Serviceguard
11.20 on HP-UX and Linux available at http://www.hp.com/go/linux-serviceguard-docs. This
paper includes instructions for setting up a sample package that uses an NFS-imported file system.
See also the description of fs_name (page 198), fs_type (page 198), and the other file
system-related package parameters.
4.9.3 Planning for Expansion
You can add packages to a running cluster. This process is described in Chapter 7: “Cluster and
Package Maintenance” (page 211).
When adding packages, be sure not to exceed the value of max_configured_packages as
defined in the cluster configuration file (see “Cluster Configuration Parameters” (page 89)). You
can modify this parameter while the cluster is running if you need to.
4.9.4 Choosing Switching and Failover Behavior
To determine the failover behavior of a failover package (see “Package Types” (page 41)), you
define the policy that governs where Serviceguard will automatically start up a package that is not
running. In addition, you define a failback policy that determines whether a package will be
automatically returned to its primary node when that is possible.
The following table describes different types of failover behavior and the settings in the package
configuration file that determine each behavior. See “Package Parameter Explanations” (page 184)
for more information.
Table 5 Package Failover Behavior
Parameters in Configuration FileSwitching Behavior
• node_fail_fast_enabled set to no. (Default)
• service_fail_fast_enabled set to no for all services. (Default)
• auto_run set to yes for the package. (Default)
Package switches normally after detection of
service or network failure, generic resource
failure or when a configured dependency is
not met. Halt script runs before switch takes
place. (Default)
• failover_policy set to min_package_node.
Package fails over to the node with the fewest
active packages.
• failover_policy set to configured_node. (Default)
Package fails over to the node that is next on
the list of nodes. (Default)
• failback_policy set to automatic.
Package is automatically halted and restarted
on its primary node if the primary node is
available and the package is running on a
non-primary node.
• failback_policy set to manual. (Default)
• failover_policy set to configured_node. (Default)
Package can be manually returned to its
primary node if it is running on a non-primary
node, but this does not happen automatically.
• 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 a specific service fails. Halt
scripts are not run.
• service_fail_fast_enabled set to yes for all services.
• auto_run set to yes for all packages.
All packages switch following a system reboot
on the node when any service fails.
106 Planning and Documenting an HA Cluster