Reverse DNS lookup

By shhite ·
We are trying to setup a reverse dns lookup on our server.

We have a Novell Domain Name Server on a Windows Server 2003 OS with Novel Client 4.** w Sp3.

We also have Pix 520 firewall which could be blocking it as well.

We are not sure whether we setup the reverse lookup correctly or how we would tell if the firewall is blocking it.




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More information

by Fregeus In reply to Reverse DNS lookup

A Novell DNS on a Windows machine. Can anyone else smell trouble already?

Anyhow, can you give us more information on what you are trying to accomplish and how you are set up.

Things like, are you trying to set up an internal reverse-lookup zone? an external? an internal that will query the external? etc.

DNS uses UDP port 53 for queries, no matter if they are name or reverse queries. If your port UDP 53 is open, it should go through your FW.

I would start by setting up an internal reverse-lookup zone for internal names and try to query it. If it works then move on to the dns forwarding or external lookups.

Let me know.


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internal vs external zone

by shhite In reply to More information

Since neither of us have a lot of knowledge about reverse lookups period I am going to guess that we want the external reverse look-up.

I will explain. We are geting messages similar to this:
Delivery failed after 1 attempts within 0 hours and 0 minutes 553 Dynamic pool. < on some of our outgoing e-mails:

We have never set up anything to do with a rdns.

Hope that is clearer to u then it is to me.

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I've seen this before

by Fregeus In reply to internal vs external zone

Yes, it is looking for a reverse-lookup address for your mail server to make sure you are who you say you are.

Are you hosting your own external DNS? If yes, then you can host your own external reverse-lookup zones. If not, then who ever is hosting your DNS can host your reverse-lookup zones. There are also a lot of Internet service providers that host the reverse-lookup zones for the IP ranges they use.

If your external IP addresses are not your own (IE where not purchased by your company but where supplied by your ISP), there is a good chance your supplier is hosting your reverse-lookup zone. If that is the case, you just need to ask them to add the IP of your mail server and all will be fixed.

Let me know if you need more info.


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Host DNS server

by shhite In reply to I've seen this before

We do host our own server but our ISP looks like they are pointing one of our ip address to them instead of to us which might be the issue. We are looking into.


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by Jellimonsta In reply to Host DNS server

Your original post stated you ran the Novell DNS on a Windows 2003 server?

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Yes I did

by shhite In reply to DNS

Did I say something different in another post? Maybe I didnt word something correctly. What are you looking at?

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by Jellimonsta In reply to Yes I did

I had initially assumed you were hosting your external DNS due to mentioning the fact you were running Novell on 2003.
You should have specified you were running internal DNS only. :)

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Got it

by shhite In reply to Yes I did

Sorry about that jm :) ... Makes sense. I will make sure to specify the difference next time. Thanks for your input! I really appreciate it.

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by Fregeus In reply to Host DNS server

Basically, if you are hosting your own reverse-lookup zone, the SOA of that zone should point the NS servers to your servers address. If one or both point to another, then they are hosting the zone or there is an error in the SOA configuration.

Let me know if you need more help.


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Take a look...

by Jellimonsta In reply to Reverse DNS lookup

At this link.

It show's the steps for reverse lookup zones.

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