Managing HP Serviceguard for Linux, Eighth Edition, March 2008

Building an HA Cluster Configuration
Configuring the Cluster
Chapter 5178
IMPORTANT Note that in this example subnet 15.244.65.0, used by NodeA and
NodeB, is not routed to 15.244.56.0, used by NodeC and NodeD.
But subnets 15.13.164.0 and 15.13.165.0, used by NodeA and NodeB,
are routed respectively to subnets 15.13.172.0 and15.13.182.0, used
by NodeC and NodeD. At least one such routing among all the nodes must
exist for cmquerycl to succeed.
For information about configuring the heartbeat in a cross-subnet
configuration, see the HEARTBEAT_IP parameter discussion under
“Cluster Configuration Parameters” starting on page 110.
Identifying Heartbeat Subnets
The cluster configuration file includes entries for IP addresses on the
heartbeat subnet. HP recommends that you use a dedicated heartbeat
subnet, and configure heartbeat on other subnets as well, including the
data subnet.
The heartbeat must be on an IPv4 subnet and must employ IPv4
addresses. An IPv6 heartbeat is not supported.
The heartbeat can comprise multiple subnets joined by a router. In this
case at least two heartbeat paths must be configured for each cluster
node. See also the discussion of HEARTBEAT_IP under “Cluster
Configuration Parameters” starting on page 110, and “Cross-Subnet
Configurations” on page 30.
Specifying Maximum Number of Configured Packages
This value must be equal to or greater than the number of packages
currently configured in the cluster. The count includes all types of
packages: failover, multi-node, and system multi-node. The maximum
number of packages per cluster is 150. The default is the maximum.
NOTE Remember to tune kernel parameters on each node to ensure that they
are set high enough for the largest number of packages that will ever run
concurrently on that node.