Managing Serviceguard Eighteenth Edition, September 2010

• 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
monitored for this package are configured for PARTIAL access, each node on the
node_name list must have at least one of these subnets configured.
— As in other configurations, a package will not start on a node unless the subnets
configured on that node, and specified in the package configuration file as
monitored subnets, are up.
NOTE: See also the Rules and Restrictions (page 39) that apply to all cluster
networking configurations.
For More Information
For more information on the details of configuring the cluster and packages in a
cross-subnet context, see “Obtaining Cross-Subnet Information” (page 248), “About
Cross-Subnet Failover” (page 201) and (for legacy packages only) “Configuring
Cross-Subnet Failover” (page 383).
See also the white paper Technical Considerations for Creating a Serviceguard Cluster that
Spans Multiple IP Subnets, which you can find at the address below. This paper discusses
and illustrates supported configurations, and also potential mis-configurations.
IMPORTANT: Although cross-subnet topology can be implemented on a single site,
it is most commonly used by extended-distance clusters, and specifically site-aware
disaster-tolerant clusters, which require Metrocluster (HP add-on software).
Design and configuration of such clusters are covered in the disaster-tolerant
documentation delivered with Serviceguard. For more information, see the following
documents underwww.hp.com/go/hpux-serviceguard-docs:
• Understanding and Designing Serviceguard Disaster Tolerant Architectures
• Designing Disaster Tolerant HA Clusters Using Metrocluster and Continentalclusters
• The white paper Configuration and Administration of Oracle 10g R2 RAC Database in
HP Metrocluster
Replacing Failed Network Cards
Depending on the system configuration, it is possible to replace failed network cards
while the cluster is running. The process is described under “Replacement of LAN
Cards” in the chapter “Troubleshooting Your Cluster.” With some restrictions, you
can also add and delete LAN interfaces to and from the cluster configuration while the
Redundant Network Components 43