Managing Serviceguard 13th Edition, February 2007

Understanding Serviceguard Software Components
How the Network Manager Works
Chapter 3114
Additional Heartbeat Requirements
VLAN technology allows great flexibility in network configuration. To
maintain Serviceguard’s reliability and availability in such an
environment, the heartbeat rules are tightened as follows when the
cluster is using VLANs:
1. VLAN heartbeat networks must be configured on separate physical
NICs or APA aggregates, to avoid single points of failure.
2. Heartbeats are still recommended on all cluster networks, including
VLANs.
3. If you are using VLANs, but decide not to use VLANs for heartbeat
networks, heartbeats are recommended for all other physical
networks or APA aggregates specified in the cluster configuration
file.