Managing Serviceguard 14th Edition, June 2007

Planning and Documenting an HA Cluster
Package Configuration Planning
Chapter 4 169
CAUTION Once you create the disk group and mount point packages, it is
critical that you administer the cluster with the cfs commands,
including cfsdgadm, cfsmntadm, cfsmount, and cfsumount. If you
use the general commands such as mount and umount, it could cause
serious problems such as writing to the local file system instead of
the cluster file system.
Any form of the mount command (for example, mount -o cluster,
dbed_chkptmount, or sfrac_chkptmount) other than cfsmount or
cfsumount in a HP Serviceguard Storage Management Suite
environment with CFS should be done with caution. These non-cfs
commands could cause conflicts with subsequent command
operations on the file system or Serviceguard packages. Use of these
other forms of mount will not create an appropriate multi-node
package which means that the cluster packages are not aware of the
file system changes.
NOTE The Disk Group (DG) and Mount Point (MP) multi-node packages
(SG-CFS-DG_ID# and SG-CFS-MP_ID#) do not monitor the health of
the disk group and mount point. They check that the application
packages that depend on them have access to the disk groups and
mount points. If the dependent application package loses access and
cannot read and write to the disk, it will fail, but that will not cause
the DG or MP multi-node package to fail.
4. You create the CFS package, SG-CFS-pkg, with the cfscluster
command. It is a system multi-node package that regulates the
volumes used by CVM 4.1 and later. System multi-node packages
cannot be dependent on any other package.
Planning for Expansion
You can add packages to a running cluster. This process is described in
Chapter 7, “Cluster and Package Maintenance,” on page 317.