Help to add a second IP 1

[rasindia]

Hi,

We have a 1721 cisco router. Currently we are using a range of public IPs given by ISP. Now we got another range of public IPs. I want to add an IP from the new range to the internal interface of the router and make it route to the current external IP. [both ranges belongs to different subnets of the ISP]This way we can make use of the new range for our new business requirements.

Can anyone tell me the steps to do this configuration? With command lines please.

Best regards
Ras

 

[chieftan999]

Normally you would just add an IP address to an Interface as follows:-

Router#conf t
Router(config)#int fa0/0 (or whatever your interface is)
Router(config-if)#ip address (IP Address) (subnet mask)
Router(config-if)#no shutdown
Router(config-if)#ctrl+z

This will set an IP address to the Interface. As from a routing perspective, you are using a layer 3 device, this shouls route automatically from one interface to the other on the same device.