Cisco Nat Pool and Overload

[dylan.keys1]

Hi All,

I have a network that has 2 ISP connection, ISP1 and ISP2. I require any data on VLAN10 to NAT Overload to ISP1 which is simple and is working fine. I now also require data on VLAN30 to dynamic NAT to a pool of public IP address on ISP2 and VLAN40 to NAT Overload to a single IP address on ISP2.

I only have one physical interface on the router which is trunking all the vlans to a core switch which has the ISP connected to the corresponding vlans.

I just wanted to know if this is the right way to do this or there are other avenues I could look at?

Cheers,

Dylan K

[Mark Mc Nicholas]

Hi Dylan,

My thoughts on this would be to look at using policy based routing. This would allow you to dictate which source vlan's go out though which default gateway(ISP).

While you will need NAT for the same reason you always have, You are best to use routing to direct the flow of traffic.

Below are links to help explain PBR 

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/12-2/25sg/configuration/guide/conf/pbroute.pdf

http://www.cisco.com/c/en/us/td/docs/ios/12_2/qos/configuration/guide/fqos_c/qcfpbr.html