Comments on: Exchange Server 2003 & Missing MX Record

By: 8087873541

8087873541 — Tue, 15 Jun 2010 02:11:32 +0000

i have register my domain also made dns entry with isp. my domain is vmail.vyommail.com but when i send mail from nitin@vyommail.com to other domain like yahoo or gmail then it works. but when i send mail from other domain to my domain that time it not works. i get an error Sorry, I couldn’t find a mail exchanger or IP address. (#5.4.4). so pls. help me out in this issue. – thanks

By: bobkberg

bobkberg — Thu, 07 Jun 2007 17:00:26 +0000

Well, you can use what astronomer suggested – it gets the same info I used, but I’m an old command-line hacker.

As for what I did and how I got it, I went into nslookup from the command-line (DOS Prompt).

Once inside nslookup, I get reminded of what my current name server is.
===================
Default Server: manzanita.networkeval.com
Address: 192.168.249.24

>
===================

At this point, I can set specific query types

set type=A (The default – looks up A records)
set type=MX (Look up MX records for a domain in the following queries)
set type=SOA (Start Of Authority – who is responsible for the queried domains)
set type=NS (Name Servers – tell me what the authoritative name servers are).

The structure of the name service records are fairly strict. The specific syntax varies according to whose name server you’re running (BIND 4, BIND 8, BIND 9, Microsoft, Cisco Network Registrar, etc.), but the information provided over the network to querying systems is always provided in the same format. I would guess that with all the misconfiguration in your records, you may have even gotten misleading error messages from other systems. The other thing is that you have to know what you’re looking for – hence my recommendation of the DNS and BIND book.

Hope that helps,

Bob

By: astronomer

astronomer — Thu, 07 Jun 2007 15:34:55 +0000

Did you try the site I recommended? You can get most of this information from this site and see how things look from the outside. Check out the down arrow on the query line. You should be able to find everything you need. When I set up our public DNS servers I used this technique to verify everything was correct from an outside perspective.
rt

By: pmiller78

pmiller78 — Thu, 07 Jun 2007 13:13:43 +0000

Hey Bob,
THanks for the info, that is very helpful. I do have another question for you though; What were youusing to get those results? I would like to see if they are any better now that some changes have been made and what you posted was alot more useful that anything else I have found so far.

By: bobkberg

bobkberg — Thu, 07 Jun 2007 12:13:07 +0000

I think you’re missing a key point here. Your (external) DNS records are not properly set up.

When you look up the SOA for msimm.com, you get:
Non-authoritative answer:
msimm.com
primary name server = webserver
responsible mail addr = admin
serial = 319673
refresh = 900 (15 mins)
retry = 600 (10 mins)
expire = 86400 (1 day)
default TTL = 3600 (1 hour)
> set type=ns

Using Yahoo.com as an example, you get:
yahoo.com
primary name server = ns1.yahoo.com
responsible mail addr = hostmaster.yahoo-inc.com
serial = 2007060707
refresh = 3600 (1 hour)
retry = 300 (5 mins)
expire = 1814400 (21 days)
default TTL = 600 (10 mins)

Your external msimm.com SOA record does not contain a complete name server, the responsible mail address, has an incomplete email (just “admin”).

Depending on which name server I use, when I do an NS (Set type=ns), I get the following for your name server records:
> msimm.com
Server: vnsc-bak.sys.gtei.net
Address: 4.2.2.2

DNS request timed out.
timeout was 2 seconds.
Non-authoritative answer:
msimm.com nameserver = webserver

== OR ==

> msimm.com
Server: primitivo.networkeval.com
Address: 192.168.249.20

Non-authoritative answer:
msimm.com nameserver = ns1.msimm.com
msimm.com nameserver = ns.msimm.com

But the latter names do NOT resolve.

Bottom Line: I could keep digging, but the key point here is that whoever is maintaining your external DNS has done more things wrong than I care to discover. I’d bet large sums of money that I could find even more if I kept going.

Recommendation: Buy a copy of DNS and BIND (Paul Albitz and Cricket Liu) O’Reilly ISBN: 0-596-00158-4, and read the chapters on setting up domains to begin with. Then make your ISP people read it. . Even if you’re using a non-BIND DNS like Microsoft’s or Cisco’s Network Registrar, the data structure is the same.

Alternately, go back to your previous ISP, since they seemed to know what they were doing, DNS-wise.

Bob

By: pmiller78

pmiller78 — Thu, 07 Jun 2007 10:31:29 +0000

Well.. the records are all there as they were before the ISP change. And the DNS should be pointing to 74.62.65.70.

By: astronomer

astronomer — Wed, 06 Jun 2007 17:47:57 +0000

I think Bob is right about the PTR. I did a reverse lookup and got rrcs-74-62-65-70.west.biz.rr.com
This doesn’t look anything like your domain.
If you want to do your own testing from outside, there are some sites for this purpose. Here is one of them: http://www.kloth.net/services/nslookup.php
Hope this helps.
rt

By: pmiller78

pmiller78 — Wed, 06 Jun 2007 17:04:16 +0000

I am running my own DNS server here in the office. I have my SOA and MX records listed. They have not changed. I did make a change from one ISP to another last week, you’d think the DNS propogation would be done by now but I guess that is a possibility. Can some of you try a nslookup on it for me and let me know what you get? mail.msimm.com should come to 74.62.65.70