Multi nic concept in vcs

Have you tried to read through the relevant sections in Bundled Agent Guide?

You download it from SORT.
VCS 6.1 docs: 
https://sort.symantec.com/documents/doc_details/sfha/6.1/Solaris/ProductGuides/  

Under Network Agents, look for Agent comparisons.

Extract:

IP and NIC agents
The IP and NIC agents:
■ Monitor a single NIC 

IPMultiNIC and MultiNICA agents
The IPMultiNIC and MultiNICA agents:
■ Monitor single or multiple NICs
■ Check the backup NICs at fail over
■ Use the original base IP address when failing over
■ Provide slower failover compared to MultiNICB but can function with fewer IP addresses
■ Have only one active NIC at a time

IPMultiNICB and MultiNICB agents
The IPMultiNICB and MultiNICB agents:
■ Monitor single or multiple NICs
■ Check the backup NICs as soon as it comes up
■ Require a pre-assigned base IP address for each NIC
■ Do not fail over the original base IP address
■ Provide faster fail over compared to MultiNICA but require more IP addresses
■ Have more than one active NIC at a time

I agree with Mike - On Solaris, config IPMP (see Oracle documentation) and use MultiNICB to monitor (see Bundled Agent Guide)