NAT and DNS

[Buddhist]

I've setup a nat configuration on a 3600 router with five internal servers connected via a switch to eth 0/1. NAT translations have been placed for all neccessary components and pinging within the system for both nat wan/ global addresses and local addresses are all succesful. The connection on eth0/0 is also pingable from the internal addresses. (connection on eth 0/0 is router to t1 csu/dsu internet service connection)

The problem i am having is trying to ping internet addresses from behind the NAT. It seems when pinging, it can't properly translate the domain name to an ip address through the internal dns server located behind eth 0/1. I've configured the router with ip name-server and the appropriate dns numbers but still this seems to be an issue.
Anyone have any idea?

Thanks for any assistance... and i recognize the above description is a bit vague... so i'll try and answer questions if anyone else has any. Thanks!

 

[skyking]

Is the internal name server set up to forward out requests to your ISP's servers? If not, and you are setting your own nameserver as the only dns on local machines, the buck stops there. It does not matter what is entered into the router, if the request is aimed at an internal server that does not have all the records or does not forward unknown domains out for resolution.

 

[Buddhist]

Thanks for your advice.

Yes, the internal DNS server is setup to forward requests to the external dns server, so that shouldn't be the problem.

Any other ideas?

 

[skyking]

do a dig or nslookup from the dns server itself. see if it can resolve a name, and work your way back. If it does not get it, no one else will.

 

[Saltin]

You can ping by IP addy, but not name, or you cant ping at all?

If you cant ping at all, your router isnt forwarding ICMP packets.

 

[Buddhist]

I got it to work.

Thank you everyone for your assistance.

 

[djdrastic]

We need solution

 

[skyking]

LOL , I was going to post the same!