Managing Serviceguard Fifteenth Edition, reprinted May 2008

Planning and Documenting an HA Cluster
Cluster Configuration Planning
Chapter 4 157
All other characters are legal. The cluster name can
contain up to 39 characters (bytes).
CAUTION Make sure that the cluster name is unique within the
subnets configured on the cluster nodes; under some
circumstances Serviceguard may not be able to detect a
duplicate name and unexpected problems may result.
In particular make sure that two clusters with the
same name do not use the same quorum server; this
could result in one of the clusters failing to obtain the
quorum server’s arbitration services when it needs
them, and thus failing to re-form.
QS_HOST The fully-qualified hostname or IP address of a host
system outside the current cluster that is providing
quorum server functionality. This parameter is used
only when you employ a quorum server for tie-breaking
services in the cluster. You can also specify an alternate
address (QS_ADDR) by which the cluster nodes can reach
the quorum server. For more information, see“Using a
Quorum Server” on page 146 and “Specifying a
Quorum Server” on page 232.
Neither this parameter nor QS_ADDR can be changed
while the cluster is running; if you need to change the
hostname or IP address of the quorum server, or the
alternate hostname or IP address, you must halt the
cluster, change the quorum server information in the
cluster configuration file and re-apply the cluster
configuration (cmapplyconf).
IMPORTANT Whether you enter an IP address or a hostname for
QS_HOST and QS_ADDR, this restriction applies to both
the address and the hostname: you must halt the
cluster to change the hostname, the IP address, or both.