DNS SERVER with public IP behind the router

Unanswered Question
Mar 1st, 2009


i want my DNS server to be accessible to the internet , ok i have poll of pulic ip address, and i have the router with serial interface configured with another public ip ,

i want to assign my server one of those public ip

should i configured the lan interface with one of them and the server with another in-same-subnet ip address

or what to do

how to overcome such scenario


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Jon Marshall Sun, 03/01/2009 - 06:37

ip nat inside source static

then on the router inside interface

int fa0/0

ip nat inside

int s0/0

ip nat outside

Edit - actually with NAT it may not be as easy as that. What addresses will the DNS server be handing out - you need to make sure it hands out public IP addresses for any requests from the Internet. It's no good handing out private IP addresses as these won't be reachable.


alaeldien Sun, 03/01/2009 - 21:07


the confusion is that how to map static route using 2 public ip

is it going to work this way ?

ip nat inside source static tcp 53 53

or ineed to create DMZ in the router if yes could you possibly please advise.

thank you



Jon Marshall Mon, 03/02/2009 - 03:00


Okay you've confused me now. Why do you need to use the serial interface address in your nat statment ?

What is the IP address of your DNS server currently ?



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