My Cisco 871 router uses DHCP to acquire a public ip address from my ISP.
This is my running config for the wan interface (stripped down to the essential):
interface FastEthernet4 ip address dhcp ip nat outside ip virtual-reassembly duplex auto speed auto no cdp enable end
But recently, I've learned that I'm actually assigned two public ip addresses by my ISP. But both of them can and will change over time. Therefore, I still need to use DHCP.
As I've got some services to publish, I would now like to use both addresses and assign the second one to the router, too. One IP for my clients (NAT) and the second one for common services like http, svn, ssh, ...
Maybe I could use a virtual interface for this somehow? Or is there something like an
ip address dhcp secondary. If I get to assign the IP, how do I differenciate between the two (for routing)
Any help is appreciated