It can be done, but you must use route-maps in your "ip nat inside source" statements instead.
The following configuration uses object tracking to fail over to a backup link. Using tracking we remove or add a default route with a lower metric into the routing table upon a particular host becomming unavailable or available, respectively. Once the primary is back up, connectivity fails back to the primary, and the secondary remains idle until the primary fails again. track 1 rtr 1 reachability ! interface Dialer1 description ** Your primary Internet connection here ** ip nat outside ! interface Dialer1 description ** Your secondary Internet connection here ** ip nat outside ! ip route 0.0.0.0 0.0.0.0 Dialer1 track 1 ip route 0.0.0.0 0.0.0.0 Dialer2 10 ip route 1.2.3.4 255.255.255.255 Dialer1 ! ip nat inside source route-map pri-nat interface Dialer1 overload ip nat inside source route-map sec-nat interface Dialer2 overload ! ip sla 1 icmp-echo 1.2.3.4 source-interface Dialer1 timeout 4500 threshold 6500 frequency 30 ip sla schedule 1 life forever start-time now access-list 100 permit ip 10.10.10.0 0.0.0.7 any access-list 101 permit ip 10.10.10.0 0.0.0.7 any dialer-list 1 protocol ip permit dialer-list 2 protocol ip permit ! route-map pri-nat permit 10 match ip address 100 match interface Dialer1 ! route-map sec-nat permit 10 match ip address 101 match interface Dialer2 ! Simply replace 1.2.3.4 with a host on the internet you would like to monitor, preferably one you wont need to actually reach when your primary link goes down, since we are explicitly routing that host via the primary ISP. Other than that, make other adjustments as required, such as interface names, subnets, etc etc. Any routes you want removed from the routing table when the primary link goes down, add "track 1" after it as per my example. They'll come back when it comes up again. My example uses dialer interfaces for the WAN connectivity, but it can easily be adapted for any other type or combination of connectivity. Cheers, Tom ----- Original Message ----- From: "Adrian Minta" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Thursday, August 16, 2007 4:05 PM Subject: [c-nsp] NAT, dual WAN and a cisco router > Is it possible to use two Internet connection with a cisco router ? > I need to have redundancy for a small NATed LAN. > > Does anyone have this configuration? > > -- > Best regards, > > Adrian Minta > > > > _______________________________________________ > cisco-nsp mailing list [email protected] > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
