Managing Serviceguard Seventeenth Edition, First Reprint December 2009

• If you don't use the -h option, Serviceguard will choose the best available
configuration to meet minimum requirements, preferring an IPv4 LAN over IPv6
where both are available. The resulting configuration could be IPv4 only, IPv6
only, or a mix of both. You can override Serviceguard's default choices by means
of the HEARTBEAT_IP parameter, discussed under “Cluster Configuration
Parameters ” (page 139); that discussion also spells out the heartbeat requirements.
• The-h and -c options are mutually exclusive.
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 224).
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 139).
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 create a lock disk, enter the lock disk information following the cluster name. 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 ASCII 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.
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
222 Building an HA Cluster Configuration