Managing Serviceguard Eighteenth Edition, September 2010

Full Network Probing
-w full lets you specify full network probing, in which actual connectivity is verified
among all LAN interfaces on all nodes in the cluster, whether or not they are all on the
same subnet.
NOTE: This option must be used to discover actual or potential nodes and subnets
in a cross-subnet configuration. See “Obtaining Cross-Subnet Information” (page 248).
It will also validate IP Monitor polling targets; see “Monitoring LAN Interfaces and
Detecting Failure: IP Level” (page 98), and POLLING_TARGET under “Cluster
Configuration Parameters ” (page 143).
Specifying a Lock Disk
A cluster lock disk, lock LUN, or Quorum Server, is required for two-node clusters.
The lock must be accessible to all nodes and must be powered separately from the
nodes. See “Cluster Lock ” (page 62)for more information.
To specify a lock disk, enter the lock disk information either on the command line, or
in the configuration file. The lock disk must be in an LVM volume group that is
accessible to all the nodes in the cluster.
The default FIRST_CLUSTER_LOCK_VG and FIRST_CLUSTER_LOCK_PV supplied
in the template created with cmquerycl are the volume group and physical volume
name of a disk connected to all cluster nodes; if there is more than one, the disk is
chosen on the basis of minimum failover time calculations. You should ensure that this
disk meets your power wiring requirements. If necessary, choose a disk powered by
a circuit which powers fewer than half the nodes in the cluster.
For more information, see the discussion of these parameters under “Cluster
Configuration Parameters ” (page 143), the cmquerycl (1m) manpage, and the
comments in the template configuration file.
To display the failover times of disks, use the cmquerycl command, specifying all the
nodes in the cluster. The output of the command lists the disks connected to each node
together with the re-formation time associated with each.
Do not include the node’s entire domain name; for example, specify ftsys9, not
ftsys9.cup.hp.com:
cmquerycl -v -n ftsys9 -n ftsys10
cmquerycl will not print out the re-formation time for a volume group that currently
belongs to a cluster. If you want cmquerycl to print the re-formation time for a volume
group, run vgchange -c n <vg name> to clear the cluster ID from the volume
group. After you are done, do not forget to run vgchange -c y vgname to rewrite
the cluster ID back to the volume group; for example:
vgchange -c y /dev/vglock
246 Building an HA Cluster Configuration