Re: DNS - nslookup & sendmail

On Aug 7, 12:36 pm, Bill Campbell <b...@xxxxxxxxxxxxx> wrote:
On Thu, Aug 07, 2008, stev...@xxxxxxxxx wrote:
On Aug 6, 9:03 pm, Bill Campbell <b...@xxxxxxxxxxxxx> wrote:
On Wed, Aug 06, 2008, stev...@xxxxxxxxx wrote:
On an SCO OSF 6 mp3 server, using Sendmail 8.13.8/8.13.8, that I will
name here as "abc.com", almost all of the email is being rejected. An
example of the error messages in syslog is:

OK, connected to abc.com...
< 220 abc.com ESMTP Sendmail 8.13.8/8.13.8; Wed, 6 Aug 2008 17:17:24
-0400 (EDT)
HELO edit.dnsvr.com
< 250 abc.com Hello [64.85.73.124], pleased to meet you
MAIL FROM:<m...@xxxxxxx>
< 553 5.1.8 <m...@xxxxxxx
... Domain of sender address m...@xxxxxxx does not exist

The domain of sender does in fact exist. A nslookup test at
zoneedit.com produeces:

Give that you're using bogus domain names, there is no way to
check what is really going on. The error ``sendor address.*does
not exist'' probably means that there are no MX or A records for
the domain (at least that what it means with postfix -- I have
always avoided sendmail like the plague :-).

...
I thought that I replied to Bill's response but I do not see it. If
this is repetitious my apologies:

I have used dig on all of the domains that I referenced and I get all
the information that would be expected.
It is only when I use nslookup that I get the odd response. Again is
I perform an nslookup while logged into the host "server.abc.com" on
the domain name "abc.com the following is returned:

#nslookup abc.com
Server: ns5.dyndns.org
Address: 203.62.195.75

Name: abc.com.abc.com
Served by:
- M.ROOT-SERVERS.NET
.........

As I pointed out in a private e-mail, the problem appears to be
with the 203.62.195.75 name server which is not returning good
data. Running the same command with a different name server
returns valid information. This is a query using our local
caching name server (dnscache from djbdns):

Server: 192.168.253.33
Address: 192.168.253.33#53

Non-authoritative answer:
Name: abc.com
Address: 199.181.132.250

dig abc.com mx

; <<>> DiG 9.5.0-P1 <<>> abc.com mx
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 25748
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;abc.com. IN MX

;; ANSWER SECTION:
abc.com. 1800 IN MX 10 mx2.disney.com.
abc.com. 1800 IN MX 10 mx3.disney.com.
abc.com. 1800 IN MX 10 mx4.disney.com.
abc.com. 1800 IN MX 10 mx1.disney.com.

;; Query time: 48 msec
;; SERVER: 192.168.253.33#53(192.168.253.33)
;; WHEN: Thu Aug 7 09:35:05 2008
;; MSG SIZE rcvd: 112

Select a working name server in /etc/resolv.conf and the problems
will probably go away.



If I perform an nslookup from the same server (server.abc.com) on
several of the domains that are being rejected by sendmail, lets call
them xyz.com, I get the following:

#nslookup xyz.com
Server: ns5.dyndns.org
Address: 203.62.195.75

Name: xyz.com.abc.com
Served by:
- D.ROOT-SERVERS.NET
.....

All rejected domains do in fact have MX records.
I have repeated queries using dig and everything looks fine. Which
gets me back to why is sendmail rejecting the email?

When I became aware of the email problem I had been using "swat" to
configure samba. I do not know if this is related or not. I will
remove the samba if need be, but first I would like to verify that
that the sendmail problem is not related to DNS.

--
Bill
--
INTERNET: b...@xxxxxxxxxxxxx Bill Campbell; Celestial Software LLC
URL:http://www.celestial.com/ PO Box 820; 6641 E. Mercer Way
Voice: (206) 236-1676 Mercer Island, WA 98040-0820
Fax: (206) 232-9186

It's not what you pay a man but what he costs you that counts.
Will Rogers

The problem has been resolved and you were correct the problem was
with several domain servers at a particular dynamic name provider. I
made the changes to our resolv.conf and notified the DNS provider of
the problem.

Thanks for your help.

Steve
.

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