HP Serviceguard for Linux Version A.11.19 Release Notes, October 2009

Configuration Tasks
Cluster and package configuration tasks are affected as follows:
• You must use the -w full option of cmquerycl to discover actual or potential
nodes and subnets across routers.
• For modular packages, you must configure two new parameters in the package
configuration file to allow packages to fail over across subnets:
— ip_subnet_node - to indicate which nodes the subnet is configured on
— monitored_subnet_access - to indicate whether the subnet is configured on all
nodes (FULL) or only some (PARTIAL)
(For legacy packages, see “Configuring Cross-Subnet Failover” in Chapter 7 of the
latest edition of Managing Serviceguard for Linux.)
• You should not use the wildcard (*) for node_name in the package configuration
file, as this could allow the package to fail over across subnets when a node on the
same subnet is eligible. Instead, list the nodes in order of preference.
Restrictions
The following restrictions apply:
• All nodes in the cluster must belong to the same network domain (that is, the
domain portion of the fully-qualified domain name must be the same).
• The nodes must be fully connected at the IP level.
• A minimum of two heartbeat paths must be configured for each cluster node.
• There must be less than 200 milliseconds of latency in the heartbeat network.
• Each heartbeat subnet on each node must be physically routed separately to the
heartbeat subnet on another node; that is, each heartbeat path must be physically
separate:
— The heartbeats must be statically routed; static route entries must be configured
on each node to route the heartbeats through different paths.
— Failure of a single router must not affect both heartbeats at the same time.
• Deploying applications in this environment requires careful consideration; see
“Implications for Application Deployment” in Chapter 4 of Managing Serviceguard
for Linux.
• cmrunnode will fail if the “hostname LAN” is down on the node in question.
(“Hostname LAN” refers to the public LAN on which the IP address that the node’s
hostname resolves to is configured).
• If a monitored_subnet is configured for PARTIAL monitored_subnet_access in a
package’s configuration file, it must be configured on at least one of the nodes on
the node_name list for that package. Conversely, if all of the subnets that are being
30 Serviceguard for Linux Version A.11.19 Release Notes