Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

problem with static NAT when Load Balancing Internet traffic!!!

One of our custome has tw0 sites: India and London.

The router are connected in the following fashion:

There is a central router connected to the LAN at each site. The central router in turn is connected to two edge routers. sa central router at mumbai is MC and edge routers are ME1 and ME2. The same at London end are LC, LE1 and LE2 respectively.

2 different ISP connect to the edge routers at each site.

Now there is a site to site VPN between LE1 and ME1 and another VPN betwen ME2 and LE1.

There are 2 default routes configured in LC and MC respectively. SLA is configured on LC and MC to determine if any ISP link is down..

The configuration works fine wen the VPN and the internet traffic is to be load balanced and there is a failover.

In India there are a few static NAT to the servers inside the LAN.One of them is a mail server which receives and sends mails.

At Mubai ISP1 NAts these servers to an IP range say 59.x.x.x and ISP 2 NATs these servers to IP 212.x.x.x.

Following are the requirements :

I want the setup to access the internet from any of the overloaded IPs of the edge routers.

When the mail server or any other server is accessed from outside the returning traffic should go from the same edge router where it came in from.

Please help me on the configuration..

The central routers on both the sides are 2811 SEC K9 and the egde routers are 2801 SEC K9


Re: problem with static NAT when Load Balancing Internet traffic

The following document has a sample configuration for "Configuring NAT to Allow Internal Users to Access the Internet Using Overloading"