topic DNS resolution problem in Operating System - HP-UX

DNS resolution problem

Kathleen — Tue, 22 Jul 2003 13:18:09 GMT

We changed the IP of our email server to an internal IP address in our network. We made the changes to our internal dns and all looks well. Only problem is, when we do an nslookup on the old outside address, the internal dns still finds a way to resolve it. I have looked in all the db files and I can't find anywhere that old IP is listed. What do I need to do to totally refresh the indns database...where could it be finding that old address. Any help would be greatly appreciated. We are using bind 9.2.0

Re: DNS resolution problem

Bill McNAMARA_1 — Tue, 22 Jul 2003 13:46:19 GMT

post your resolv.conf file?

Re: DNS resolution problem

Kathleen — Tue, 22 Jul 2003 13:48:31 GMT

It shows our domain name and the ip of our internal dns

Re: DNS resolution problem

Steven E. Protter — Tue, 22 Jul 2003 13:48:32 GMT

This is dependent on two things:

1) The contents of the Master DNS record. Are they correct?

2) How the machines resolve. If they are unix, /etc/resolv.conf

My guess based on experience is that you've got machines pointing to some secondary DNS server that is not updated.

SEP

Re: DNS resolution problem

Mark Greene_1 — Tue, 22 Jul 2003 14:06:19 GMT

You need to add a "forwarders" statement to you /etc/named.conf file to include the IP addresses (not the names!) of your ISP's DNS servers.

mark

Re: DNS resolution problem

Paul Sperry — Tue, 22 Jul 2003 14:13:54 GMT

try adding the address in you /etc/hosts file.

also make sure in the /etc/nsswitch.conf
you have the following entry:

hosts: files [NOTFOUND=continue] dns

Re: DNS resolution problem

Kathleen — Tue, 22 Jul 2003 14:19:27 GMT

The internal resolves fine.....it resolves to the outside address too....which is what we DON'T want to happen. So it shouldn't be in hosts, right? Which were you talking about adding to the hosts file?

Re: DNS resolution problem

Mark Greene_1 — Tue, 22 Jul 2003 14:29:28 GMT

Kathleen,

Yes, take any external hosts you do not want to be resolved out of both the /etc/hosts file and out of your internal DNS tables. If you don't want any external hosts being resolved, then *remove* the forwarders line from the /etc/named.conf, if it exists.

mark

Re: DNS resolution problem

Ron Kinner — Tue, 22 Jul 2003 17:22:18 GMT

nslookup
set debug
emailservername

(note results)

set norec
set nosearch
emailservername

set type=any
emailservername

The results should tell you where the old ip is coming from.

Ron

Re: DNS resolution problem

Jason Martens — Tue, 22 Jul 2003 17:29:50 GMT

Make sure you removed the old entry from the reverse lookup too.