Connection refused from local mail server

[Steve3]

Hi all,

I'm testing ZCS Network edition in my company right now. My current mail server still exists at mail.domain.com, and the ZCS server is at zimbra.domain.com.

From external addresses (gmail, .mac), I can send to username@zimbra.domain.com exactly as I'd expect to. But if I go to my existing mail server and send to the same username@zimbra.domain.com, it's:

stat=Deferred: Connection refused by zimbra.domain.com

How do I determine why the connection is refused?

I've added the LAN to the MTA trusted networks (via configuration: servers: MTA).
I'm trying to deliver mail to a recipient on that domain... I can't see why it would refuse.

Thanks,
Steve.

[phoenix]

Welcome to the forums.

Do you have local DNS A & MX records pointing to your zimbra server? You may need to review the split DNS & split domain sections of the wiki.

[Steve3]

Hi Phoenix,

Yes, I do have A and MX records. If you ask either machine to dig or host itself or the other, you see that it has the right (internal) address, and lists the mx record (in the format zimbra.domain.com mail is handled by 10 zimbra.domain.com).

What catches my eye is when I watch the existing mail server logs, it's trying to connect to the external IP of zimbra.domain.com, which doesn't make much sense. The external IP doesn't show in dig or host, and I ran sendmail -bH to purge sendmail's host database, but nothing changed.

I'm running my zimbra server on OS X. I see that the split DNS instructions are for RHEL. I added a forwarders entry within the options block with my best interpretation of the instructions, but my results are the same.
Is there a service I need to restart to get my changes to named.conf to be recognized?

[DVan]

I would also look at the DNS entires listed for your local mail server and make sure you have proper DNS resolution from the Zimbra server, and that the mail server is appropropriately sending the proper hostname information.

Zimbra out of the box comes with several options preconfigured to limit your exposure to spam, which works really great. Unfortunately I found some of these too restrictive as many people have misconfigured email servers, and our zimbra server was rejecting them.

run a "zmprov gacf |grep zimbraMtaRestriction"

to see what restrictions you currenlty have in place. I personally had to remove the "zimbraMtaRestriction reject_non_fqdn_hostname" setting as it was keeping us from getting legitimate mail from misconfigured mail servers incorrectly reporting their hostname as something like "stupidserver.local".

Good Luck.

[Steve3]

No MTA restrictions. I turned those off in the GUI during my troubleshooting of this, and none show up from a zmprov gacf.

[phoenix]

What catches my eye is when I watch the existing mail server logs, it's trying to connect to the external IP of zimbra.domain.com, which doesn't make much sense. The external IP doesn't show in dig or host, and I ran sendmail -bH to purge sendmail's host database, but nothing changed.

If that's the cas then you have something misconfigured. What do the following show (on the zimbra server):

host `hostname` - type exactly with backticks
dig yourdomain.com any

and lets see what they say.

[Steve3]

Done on the zimbra server:

zimbra$ host `hostname`
zimbra.domain.com has address 192.168.6.4
zimbra.domain.com mail is handled by 10 zimbra.domain.com.
zimbra:/Users/apple zimbra$

and

zimbra:/Users/apple zimbra$ dig domain.com any

; <<>> DiG 9.3.4 <<>> domain.com any
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 43546
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 5, AUTHORITY: 0, ADDITIONAL: 2

;; QUESTION SECTION:
;domain.com.                   IN      ANY

;; ANSWER SECTION:
domain.com.            600     IN      A       192.168.6.15
domain.com.            600     IN      A       192.168.6.13
domain.com.            3600    IN      NS      thg-sql-server.domain.com.
domain.com.            3600    IN      SOA     thg-sql-server.domain.com. admin. 1205 900 600 86400 3600
domain.com.            3600    IN      MX      10 mail.domain.com.

;; ADDITIONAL SECTION:
thg-sql-server.domain.com. 3600 IN     A       192.168.6.13
mail.domain.com.       3600    IN      A       192.168.6.10

;; Query time: 3 msec
;; SERVER: 192.168.6.13#53(192.168.6.13)
;; WHEN: Sat Jun  2 07:52:16 2007
;; MSG SIZE  rcvd: 184

Yes, I am doing a search and replace of the real domain for 'domain', but otherwise, this is the results.

[Steve3]

So is there nowhere in the zimbra logs to see for what reason it refused a connection from another server?

[Steve3]

Nevermind. This wasn't zimbra's issue. Once I restarted sendmail on the existing mail server, it got its DNS resolution straightened out, and all the queued email came right over.

Thanks to those who gave troubleshooting ideas. As a potential customer, it's nice to see the forums are helpful.