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New Member

NAT Trouble

I have a serial ip of 160.x.x.x and a pool of 25 IP's e0 207.x.x.x/25 on a 2620. I need to setup up nat and make all of my internal IP's Class c Private. I also need to 207.x.x.10 to point to an internal mail server at Any help would be greatly appreciated.

New Member

Re: NAT Trouble

How many internal PCs do you have? Less than 20?

Here's an example of a setup for one static NAT (mail server) and PAT (port address translation).

interface serial0

ip address 160.x.x.x

ip nat outside


interface ethernet0

ip address

ip nat inside


ip nat inside source static 207.x.x.1

ip nat inside source list 1 pool nat-pool overload

ip nat pool nat-pool netmask

access-list 1 deny

access-list 1 permit

Like I said... this is just an example, but it should give you a start.

If you have less than 20 PCs, you can make the pool equal to the number of PCs you have like:

ip nat pool nat-pool 207.x.x.3 207.x.x.18 netmask

and omit the "overload" from the "ip nat inside source list" config directive.


PS... should have used 192.168 instead of 10.x for your case, but I spaced... :)


Re: NAT Trouble

This should do it

interface ethernet 0

ip address x.x.x.x

ip nat inside


interface serial 0

ip address 160.x.x.x

ip nat outside


ip nat pool ovrld 207.x.x.x-207.x.x.x prefix 25

ip nat inside source list 1 pool ovrld overload

ip nat inside source static tcp 207.x.x.10 25


access-list 7 permit