Managing HP Serviceguard for Linux, Tenth Edition, September 2012

In addition, you should observe the following guidelines.
• CacheFS and AutoFS should be disabled on all nodes configured to run a package
that uses NFS mounts.
For more information, see the NFS Services Administrator's Guide HP-UX 11i version
3 at http://www.hp.com/go/hpux-networking-docs.
• HP recommends that you avoid a single point of failure by ensuring that the NFS
server is highly available.
NOTE: If network connectivity to the NFS Server is lost, the applications using the
imported file system may hang and it may not be possible to kill them. If the package
attempts to halt at this point, it may not halt successfully.
• Do not use the automounter; otherwise package startup may fail.
• If storage is directly connected to all the cluster nodes and shared, configure it as
a local file system rather than using NFS.
• 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 11i v3 which you can find at http://www.hp.com/go/
hpux-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 221), fs_type (page 222), and the other file
system-related package parameters.
Planning for Expansion
You can add packages to a running cluster. This process is described in Chapter 7:
“Cluster and Package Maintenance” (page 233).
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 103)). You can modify this parameter while the cluster
is running if you need to.
Choosing Switching and Failover Behavior
To determine the failover behavior of a failover package (see “Package Types” (page 44)),
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.
124 Planning and Documenting an HA Cluster