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Help with NAT on Gre tunneled subnet

Hi Experts,

I need help with Nat ( or PAT ) to the public IP's that I am getting through the gre tunnel. Attached is the topology of the network. I have two locations , with router A and router B. On the location at router B , I donot have addtional Public Ip's that are available through the ISP but i have enough IP's at router A location. In the attached diagram , I have a gre tunnel between the two sites and have managed to push the subnet from router a to router b. now the server in location B can easily use the public ip's that I get on router A , The traffic from the server goes to the internet from location router b and then the reply is sent to router a which then pushes the traffic into the GRE tunnel to complete the connection and it works fine.

I now need to set PAT on router B , but wants it to use the same subnet that is routed through the GRE tunnel from Router A.

I tried to set it up the following on Router B :-

server add

access-list 77 permit

ip nat pool mypool 59.56.x.30 59.56.x.60 netmask

ip nat inside source list 77 pool mypool overload

int gig 0/2.1 ( connected to the servers )

ip nat inside

int tunnel 50   ( doesn't work ) ..... or   int gig 0/1 ( connected to internet on router b )

ip nat outside                                     ip nat outside

How do I make this NAT work with public IP's coming from Gre Tunnel.

please help.


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