Policy Based NAT help?

[lowfell]

currently have an 1841 with an adsl interface going to the internet with a public static nat to 10.1.1.1 for the inside. Currently ALL traffic goes OUT of the D0 adsl interface which is becoming congested.
To alleviate the congestion a separate 2mb leased line is being brought online, but this has a different network to the ADSL line. I am going to connect the new leased line router to my existing 1841 by using the spare ethernet port on the 1841 & a crossover cable to the 1721 leased line router.

My issue is this.
I want to use Policy based routing to route both mail & PPTP traffic down the new leased line & all other traffic down the existing ADSL line.

HOW do I configure the NAT part of this, as I only have ONE inside address of 10.1.1.1 which ALREADY has a one to one nat for the ADSL?

I need some kind of policy based NAT for my pptp traffic & my SMTP traffic for the 10.1.1.1 address as well as leaving the existing Static nat which points to the adsl router.

Can this be done, or is it impossible?

I HAVE ALREADY LOOKED AT PBR LINKS ON THE CISCO SITE AND CANNOT FIND AN EXAMPLE!

 

[sirlollypop]

It looks like you are trying policy based routing. The natting is dependant on which interface you are have the inside & outside configured on, and any acl.

i.e the inside will be the Ethernet of the 1841 Outside the Dialer interface

So a packet going in the ethernet the routed to the other ethernet based on its source address will not be natted.(unless you configure that interface as an outside)

On the 1720 you can configure more nat. Do you use Pat on the out side of the 1721? So you have 2 public addresses one on the DSL & the other on the LL.

Also you won't nat to 10.1.1.1 as this is a non public routed address. But currently every packet leaving your router gets the same source IP address only the source port will be different. That is PAT or Overload NAT.

& everything is possible