Cisco Cisco NAC Appliance 4.9.1 Installation Guide

The Configuration Utility script requires that the CAM and CAS machines come with eth0 (NIC1) and 
eth1 (NIC2) interfaces by default and prompts you to configure these during initial installation. If your 
system has additional network interface cards (e.g. NIC3, NIC4), you can use the following 
instructions to configure the additional interfaces (e.g. eth2, eth3) on those cards. Typically, eth2 needs 
to be configured when setting up CAS systems for High Availability. For HA, once the eth2 (NIC3) 
interface is configured with the proper addressing, it can then be configured as the dedicated UDP 
heartbeat interface for the HA-CAS.

For Cisco NAC Appliance hardware platforms, the following instructions assume that the 
NIC is plugged in and “working” (i.e. recognized by BIOS and by Linux). 

To verify that the NIC has been recognized by Linux, type

 (where n is the 

interface number). For example, if adding a NIC to a system that already has two built-in 
Ethernet interfaces (eth0 and eth1), n is 2 and you enter 

.

You should see information about the interface including MAC address, and transmit and 
receive counters. This means the interface is recognized by Linux and can be used. 

Change to the following directory:

Use vi to edit the

 file for the interface, for example:

Add the following lines into the file—replacing 

, 

, 

, and 

 values 

with the actual values suitable for your network:

Save the file and reboot the system. The network interface is now ready to be used for HA.