Managing HP Serviceguard for Linux, Eighth Edition, March 2008

Planning and Documenting an HA Cluster
Cluster Configuration Planning
Chapter 4 111
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 name or IP address of a host system outside the
current cluster that is providing quorum server
functionality. This parameter is not used if
CLUSTER_LOCK_LUN is used. The QS_HOST name can
contain up to 39 bytes.
QS_POLLING_INTERVAL
The time (in microseconds) between attempts to
contact the quorum server to make sure it is running.
Default is 300,000,000 microseconds (5 minutes).This
parameter is not used if CLUSTER_LOCK_LUN is used.
QS_TIMEOUT_EXTENSION
The quorum server timeout is the time during which
the quorum server is not communicating with the
cluster. After this time, the cluster will mark the
quorum server DOWN. This time is calculated based on
Serviceguard parameters, but you can increase it by
adding an additional number of microseconds as an
extension.
The QS_TIMEOUT_EXTENSION is an optional parameter.
A value higher than NODE_TIMEOUT will increase the
failover time. This parameter is not used if
CLUSTER_LOCK_LUN is used.