Checklist for Using MultiNICB
Prev	Network agents	Next

---

Checklist for Using MultiNICB

For the MultiNICB agent to function properly, you must satisfy each item in the following list:

• Each interface must have a unique MAC address.
• A MultiNICB resource controls all the interfaces on one IP subnet.
• At boot time, you must plumb all the interfaces that are under the MultiNICB resource and give them test IP addresses.
• All test IP addresses for the MultiNICB resource must belong to the same subnet as the virtual IP address.

  Tip   The base IP addresses, which the agent uses to test the link status, should be reserved for use by the agent. These IP addresses do not get failed over.

• If NetworkHosts is specified, the hosts must be directly accessible on the LAN.

Trigger Script

MultiNICB monitor agent function calls a VCS trigger in case of an interface going up or down. The following arguments are passed to the script:

• MultiNICB resource name
• device whose status changed (for example, lan0)
• device's previous status (0 for down, 1 for up)
• device's current status
• monitor heartbeat

The agent also sends a notification (which may be received via SNMP or SMTP) to indicate that status of an interface changed. The notification is sent using "health of a cluster resource declined" and "health of a clusterresource improved" traps which are mentioned in the VCS User's Guide. A sample mnicb_postchange trigger is provided with the agent. The user may customize this sample script as needed or write one from scratch.

The sample script does the following:

• If interface changes status, it prints a message to the console, for example: MultiNICB: Device lan0 status changed from DOWN to UP.
• The script saves last IP address-to-interface name association. If any of the IP addresses has been moved, added, or removed, it prints out a message to the console, for example: MultiNICB: IP address 192.4.3.3 moved from interface lan1:1 to interface lan0:1