[SOLVED] Deferred Messages to only 1 Domain

[r8escjohn]

This one has me stumped.
Zimbra 5.0.18 FOSS that I updated a few weeks back now. Everything seems to be working ok, however there is one domain that we are not able to send to for the last week or so. We can send to anyone else and receive from this one Domain, but everything t hat is sent to it gets deferred. Zimbra log of pertinent info below:

Jul 23 15:43:02 zimbra postfix/smtp[23781]: connect to smtp.xxxx.k12.in.us[xxx.xxx.132.4]: Connection timed out (port 25)
Jul 23 15:43:02 zimbra postfix/smtp[23781]: C15B42EC034: to=<xxxx.xxxxx@xxxx.k12.in.us>, relay=none, delay=32, delays=1.2/0.44/30/0, dsn=4.4.1, status=deferred (connect to xxxx.xxxx.k12.in.us[xxx.xxx.132.4]: Connection timed out)
Jul 23 15:43:02 zimbra postfix/smtp[23783]: connect to smtp.xxxx.k12.in.us[xxx.xxx.132.4]: Connection timed out (port 25)
Jul 23 15:43:02 zimbra postfix/smtp[23783]: F2F782EC045: to=<xxxx.xxxxx@xxxx.k12.in.us>, relay=none, delay=31, delays=1.2/0.04/30/0, dsn=4.4.1, status=deferred (connect to xxxx.xxxx.k12.in.us[xxx.xxx.132.4]: Connection timed out)
Jul 23 15:43:02 zimbra postfix/qmgr[14402]: warning: connect to transport retry: No such file or directory
Jul 23 15:43:02 zimbra postfix/qmgr[14402]: warning: connect to transport retry: No such file or directory
Jul 23 15:43:03 zimbra postfix/qmgr[14402]: 5DE6D2EC04B: to=<xxxx.xxxxx@xxxx.k12.in.us>, relay=none, delay=31, delays=0.43/30/0/0, dsn=4.3.0, status=deferred (mail transport unavailable)
Jul 23 15:43:03 zimbra postfix/qmgr[14402]: D06592EC041: to=<xxxx.xxxxx@xxxx.k12.in.us>, relay=none, delay=30, delays=0.52/30/0/0, dsn=4.3.0, status=deferred (mail transport unavailable)
Jul 23 15:43:03 zimbra postfix/qmgr[14402]: 581BD2EC046: to=<xxxx.xxxxx@xxxx.k12.in.us>, relay=none, delay=30, delays=1.9/28/0/0, dsn=4.3.0, status=deferred (mail transport unavailable)
Jul 23 15:43:03 zimbra postfix/qmgr[14402]: 97B2E2EC038: to=<xxxx.xxxxx@xxxx.k12.in.us>, relay=none, delay=28, delays=0.5/27/0/0, dsn=4.3.0, status=deferred (mail transport unavailable)
Jul 23 15:43:03 zimbra postfix/qmgr[14402]: 6DAEB2EC03E: to=<xxxx.xxxxx@xxxx.k12.in.us>, relay=none, delay=27, delays=1.3/26/0/0, dsn=4.3.0, status=deferred (mail transport unavailable)
Jul 23 15:43:03 zimbra postfix/qmgr[14402]: 243F62EC036: to=<xxxx.xxxxx@xxxx.k12.in.us>, relay=none, delay=25, delays=0.62/25/0/0, dsn=4.3.0, status=deferred (mail transport unavailable)

I have tried doing a 'zmcontrol start/stop' and 'postfix reload' but issue persists. Mail to/from other domains seems to be flowing without any issues...
In my Admin UI I keep 'Flush'ing and 'Requeue'ing hoping that these messages will go but no such luck...

On a possibly related issue I see quite a few of these postfix messages in my zimbra.log also - which probably are not good.

Jul 23 20:09:30 zimbra postfix/postqueue[6530]: fatal: Queue report unavailable - mail system is down

On that, my 'zmcontrol status' shows all services running....

I have also checked my DNS and hostname on my server and all seems well as my reverse and MX records are there and out on the 'net as normal, at least for my stuff. Any thoughts on where to start with this issue?

[phoenix]

It's getting deferred because of this:

Jul 23 15:43:02 zimbra postfix/smtp[23783]: connect to smtp.xxxx.k12.in.us[xxx.xxx.132.4]: Connection timed out (port 25)

Can you try and do a telnet:

telnet smtp.xxxx.k12.in.us 25
telnet xxx.xxx.132.4 25

If neither of those work then I'd check your firewall and DNS records to make sure they point to the correct server.

[veronica]

Problem is with smtp.xxxx.k12.in.us[xxx.xxx.132.4] domain and not your.

[r8escjohn]

One 'minor' detail I left out was that when trying to telnet to this site I get nowhere from either my Zimbra box or other boxes either inside or outside my network.....

zimbra:~ # telnet smtp.xxxx.k12.in.us 25
Trying xxx.xxx.132.4...
telnet: Unable to connect to remote host

I had discounted that as thinking of this being a graylisting/spam prevention method being used at their end and also the other postfix error I am seeing in my logs

Jul 23 20:09:30 zimbra postfix/postqueue[6530]: fatal: Queue report unavailable - mail system is down

Should I not discount not being able to telnet to a smtp server?? May be a basic question, however with all of the spam prevention techniques that folks are using out there it was my understanding that a telnet connection is not always a solid test, at least as solid test as it was in the past in dealing with SMTP issues. Thanks for everybodys answers to my posting as it is greatly appreciated! :->

[uxbod]

PM me the domain you are attempting to contact please.

[phoenix]

The easiest test is to run an external test at somewhere like: Quick Check - Pingability.com - just enter the domain name and see if it connects to their server.

[uxbod]

telnet xxxx.xxxx.xxxx.in.us 25
Trying xxxx.xxxx.xxxx.4...
Connected to xxxx.xxxx.xxxx.in.us (xxx.xxx.xxx.4).
Escape character is '^]'.
220 *************************
helo xyz.com
250 xxxx.xxxx.xxxx.in.us Ok

Well it appears to connect just fine so I would check your firewall to ensure outbound packets are allowed.

[r8escjohn]

UXBOX,
First, your assistance is *greatly* appricated! :->
I can e-mail their site from both Yahoo and G-Mail without any issues so I assumed your telnet would go through fine.....
This issue is going from odd to just plain strange.....
There are two other orgs on the same provider net (Acording to traceroute) that I can Telnet (and send/receive mail from) to/from my Zimbra box just oki-doki fine all day long. Checked my PIX logs and telnet traffic is not being blocked at least from my end to theirs. At this point I am concluding there is something very odd between my Net and theirs.....Like some sort of blacklist on their box preventing access from my net. Luckley we have a good relationship with the other party and he is checking their equipment but not finding anything as of yet....Just very, very odd.....
I will keep looking on my end.
Any thoughts on my comment about telnet not being a good test lately due to all of the spam preventation/graylisting stuff out there that folks are using?
Just wondering......

[uxbod]

Originally Posted by r8escjohn

Any thoughts on my comment about telnet not being a good test lately due to all of the spam preventation/graylisting stuff out there that folks are using? Just wondering......

You should still get a response from the MTA. Even if they are greylisting all you would get, if you put through a synthetic message, would be a temporary failure notice.

[r8escjohn]

It turns out issue was at their end. Apearently after adding a single T1 from another provider to their existing DS3 setup it messed up some of the routes.....Odd as the traceroutes kept going through same path....anyway, issue is now resolved and mail is now flowing again to this doamin.
Thanks to all who replied. :->