Managing Serviceguard Sixteenth Edition, March 2009

NOTE: Limitations:
• Because Veritas Cluster File System from
Symantec (CFS) requires link-level traffic
communication (LLT) among the nodes,
Serviceguard cannot be configured in
cross-subnet configurations with CFS alone.
But CFS is supported in specific cross-subnet
configurations with Serviceguard and HP
add-on products; see the documentation
listed under “Cross-Subnet Configurations”
(page 41) for more information.
• IPv6 heartbeat subnets are not supported in
a cross-subnet configuration.
Considerations for CVM:
• If you will be using Veritas CVM 4.1 or later,
multiple heartbeats are permitted, and you
must configure either multiple heartbeat
subnets or a single heartbeat subnet with a
standby. HP recommends multiple
heartbeats.
• If you will be using CVM 3.5, however, you
can only use a single heartbeat subnet; in
this case, configure the heartbeat either with
a standby LAN or as a group of aggregated
ports on each node. If you use aggregated
ports (APA), HP recommends using Hot
Standby mode to eliminate the single point
of failure (SPOF) that a single switch
represents. See Chapter 3 of the HP Auto Port
Aggregation Administrator’s Guide at
http://docs.hp.com -> I/O Cards
and Networking Software -> Auto
Port Aggregation (APA) for more
information. A standby LAN always uses
two switches and thus does not entail a
SPOF.
• You cannot change the heartbeat
configuration while a cluster that uses CVM
is running.
• You cannot use an IPv6 heartbeat subnet
with CVM or CFS.
Cluster Configuration Planning 147