Cisco switches

Separate subnets are used, so that routing is handled correctly. Use a layer 3-capable switch and create the subnets on different VLANs. Then route the Secondary NIC on the CIC servers (10.60.0.2 and 10.60.0.3) over the WAN so that they can communicate. It is not necessary for the CIC servers to reside in the same numeric VLAN.

To create VLANs with different subnets:

In the switch CLI (telnet or other connection), enter the following configuration commands, one on each line. End with Ctrl+Z.

3560# configure terminal
3560(config)# int vlan 1
3560(config-if)# ip address 10.70.0.1 255.255.0.0
3560(config-if)# exit
3560(config)# ip default-gateway 10.70.0.6
3560(config)# end
3560(config)# int vlan 2
3560(config-if)# ip address 10.60.0.1 255.255.0.0
3560(config-if)# exit

In this example, two VLANs are created and assigned a subnet range of 10.70.x.x. and 10.60.x.x. Also a default gateway is created for the switchover.

Place the port that is connected to your SwitchoverServer NIC into its own VLAN. In this example, the SwitchoverServer is using FastEthernet 0/24. FastEthernet 0/24 plugs into the CIC servers Second NIC (Example 10.60.0.2)

3560(config)# int fastEthernet 0/24
3560(config-if)# switchport access vlan 2

You can place the primary NIC on VLAN 1 as you normally do (Example: FastEthernet 0/23).