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NAT - Many to One - Specific natting on Source IP Address

Hello Gurus I've got a NAT question

Plan - The config below refers to .22 as a host - this is for example only.

Hosts in should be able to ping etc to hosts, and hosts in should be able to ping etc to

This is natted to

So, referring to the enclosed diagram, I have in a test lab, scenario '1', whereby host can ping, and host can ping

This works by way of placing an IP NAT OUTSIDE SOURCE STATIC command on ROUTER 'A',

ip nat outside source static

and placing IP NAT INSIDE SOURCE commands on ROUTER 'B'.

ip nat pool 33 prefix-length 30

ip nat inside source route-map 22 pool 33

access-list 100 permit ip

route-map 22 permit 10

match ip address 100

This is all fair and well, but in the real world I only have access to ROUTER 'B', as per scenario '2'.

So the question is :- 'How do I do destination specific Natting on router B, so hosts in subnet 11 can speak to subnet 22, and 12 can speak to 33.'

Any help gratefully received.


Everyone's tags (1)

Hi Stephen, In your case you

Hi Stephen,


In your case you can make hosts behind the router to talk to hosts behind router A..... if the hosts behind the router A is configured with one to one mapping or with one ip with port-forwarding for multiple service ports..... Because until and unless you have a permanent fixed ip/service you cannot do so..... same way it is applicable for vice-versa....


say if you ping it responds to the ping... because it has fixed ip address for the yahoo server....





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