Sending mail to china (!) fails with SMTP 551 error...

[tommy]

One of the most peculiar things is happening to a client of ours:

About 30 email messages from and to certain chinese mail servers failed to deliver today, with the following errors:

Zimbra admin mailbox:

Errors

2007-07-16 23:50:39 deferred (lost connection with mail.shaidc.com[218.78.208.139] while sending message body)
2007-07-16 12:08:33 bounced (host mx04.263.net[124.200.240.28] said: 551 User not local; please try <forward-path> (in reply to RCPT TO command))
2007-07-16 10:33:57 deferred (lost connection with mail.shaidc.com[218.78.208.139] while sending RCPT TO)
2007-07-16 10:33:56 bounced (host mail.shaidc.com[218.78.208.139] said: 551 User not local; please try <forward-path> (in reply to RCPT TO command))
2007-07-16 08:59:40 deferred (lost connection with mx.vip.163.com[202.108.5.193] while sending end of data -- message may be sent more than once)
2007-07-16 23:50:33 deferred (lost connection with mail.longerfashion.com[218.75.110.132] while sending message body)
2007-07-16 08:44:45 deferred (lost connection with mx.mail.163.split.netease.com[220.181.12.62] while sending message body)
2007-07-16 23:50:34 deferred (lost connection with mail.shaidc.com[218.78.208.139] while sending end of data -- message may be sent more than once)
2007-07-16 23:50:37 deferred (lost connection with mx.vip.163.com[202.108.5.193] while performing the initial protocol handshake)
2007-07-16 23:50:37 deferred (lost connection with mx.mail.163.split.netease.com[220.181.12.60] while sending end of data -- message may be sent more than once)
2007-07-16 23:50:44 deferred (lost connection with mx.vip.163.com[202.108.5.190] while sending message body)
2007-07-16 20:05:32 bounced (host mail.shaidc.com[218.78.208.139] said: 551 User not local; please try <forward-path> (in reply to RCPT TO command))
2007-07-16 23:50:33 deferred (lost connection with mail.longerfashion.com[218.75.110.132] while sending end of data -- message may be sent more than once)
2007-07-16 11:39:36 bounced (host mail.shaidc.com[218.78.208.139] said: 551 User not local; please try <forward-path> (in reply to RCPT TO command))
2007-07-16 08:46:34 deferred (lost connection with mail.longerfashion.com[218.75.110.132] while sending MAIL FROM)
2007-07-16 08:29:36 deferred (lost connection with mail.shaidc.com[218.78.208.139] while sending end of data -- message may be sent more than once)
2007-07-16 08:35:32 deferred (lost connection with mx.vip.163.com[202.108.5.193] while sending end of data -- message may be sent more than once)
2007-07-16 23:50:38 deferred (lost connection with mx.mail.163.split.netease.com[220.181.12.74] while sending end of data -- message may be sent more than once)
2007-07-16 08:19:30 deferred (lost connection with mx.vip.163.com[202.108.5.193] while sending end of data -- message may be sent more than once)
2007-07-16 23:50:36 deferred (lost connection with mx.zjip.com[202.101.172.203] while sending end of data -- message may be sent more than once)
2007-07-16 23:50:43 deferred (lost connection with mx.mail.163.split.netease.com[220.181.12.72] while sending RCPT TO)
2007-07-16 23:50:33 deferred (lost connection with mx.mail.163.split.netease.com[220.181.12.71] while sending message body)
2007-07-16 23:50:39 deferred (lost connection with mx2.cnm.cn[59.151.23.106] while sending MAIL FROM)
2007-07-16 11:39:38 bounced (host mail.shaidc.com[218.78.208.139] said: 551 User not local; please try <forward-path> (in reply to RCPT TO command))
2007-07-16 23:50:41 deferred (lost connection with mx.vip.163.com[202.108.5.190] while sending message body)
2007-07-16 23:50:37 deferred (lost connection with mx.mail.163.split.netease.com[220.181.12.66] while sending message body)
2007-07-16 11:39:32 bounced (host mail.shaidc.com[218.78.208.139] said: 551 User not local; please try <forward-path> (in reply to RCPT TO command))
2007-07-16 23:50:43 deferred (lost connection with mail.longerfashion.com[218.75.110.132] while sending message body)
2007-07-16 23:50:41 deferred (lost connection with mx.vip.163.com[202.108.5.190] while sending DATA command)
2007-07-16 23:50:47 deferred (lost connection with mx.vip.163.com[202.108.5.193] while performing the initial protocol handshake)
2007-07-16 01:30:02 bounced (fast2.info)
2007-07-16 01:35:27 bounced (fast2.info)
2007-07-16 01:35:59 bounced (fast2.info)
2007-07-16 01:54:59 bounced (fast2.info)
2007-07-16 23:50:44 deferred (lost connection with mx.mail.163.split.netease.com[220.181.12.67] while sending message body)
2007-07-16 11:53:36 bounced (host mail.shaidc.com[218.78.208.139] said: 551 User not local; please try <forward-path> (in reply to RCPT TO command))
2007-07-16 11:26:14 deferred (lost connection with mail.shaidc.com[218.78.208.139] while sending end of data -- message may be sent more than once)
2007-07-16 23:50:40 deferred (lost connection with mx2.cnm.cn[59.151.23.106] while sending MAIL FROM)
2007-07-16 23:50:42 deferred (lost connection with mail.shaidc.com[218.78.208.139] while sending end of data -- message may be sent more than once)
2007-07-16 18:16:40 deferred (lost connection with mx.vip.163.com[202.108.5.193] while performing the initial protocol handshake)
2007-07-16 23:22:28 bounced (host linuxserver.linuxnet.tx[192.168.0.77] said: 550 5.1.1 No such user here (in reply to RCPT TO command))
2007-07-16 20:01:31 deferred (host g.mx.mail.yahoo.com[206.190.53.191] said: 451 Message temporarily deferred - [190] (in reply to end of DATA command))
2007-07-16 13:33:37 bounced (host gmail-smtp-in.l.google.com[64.233.183.27] said: 552 5.7.0 Illegal Attachment f4si32391278nfh (in reply to end of DATA command))
2007-07-16 22:17:42 deferred (host g.mx.mail.yahoo.com[209.191.88.239] said: 451 Message temporarily deferred - [170] (in reply to end of DATA command))
2007-07-16 16:47:13 deferred (lost connection with mx.vip.163.com[202.108.5.189] while sending DATA command)
2007-07-16 11:56:12 deferred (host g.mx.mail.yahoo.com[206.190.53.191] said: 451 Message temporarily deferred - [190] (in reply to end of DATA command))

Zimbra logs (snip):

Jul 17 01:56:43 linuxserver postfix/smtp[3701]: EE0165691A4: to=<xxxx@163.com>, relay=mx.mail.163.split.netease.com[220.181.12.59], delay=7559, status=deferred (lost connection with mx.mail.163.split.netease.com[220.181.12.59] while sending message body)
Jul 17 01:56:40 linuxserver postfix/smtp[3704]: BD47B5691A5: to=<xxxx@longerfashion.com>, relay=mail.longerfashion.com[218.75.110.132], delay=7563, status=deferred (lost connection with mail.longerfashion.com[218.75.110.132] while sending end of data -- message may be sent more than once)
Jul 17 01:56:37 linuxserver postfix/smtp[3712]: 987AB5691A0: to=<xxxx@vip.163.com>, relay=mx.vip.163.com[202.108.5.190], delay=7556, status=deferred (lost connection with mx.vip.163.com[202.108.5.190] while performing the initial protocol handshake)

All of these are chinese domains, meanwhile mail with attachments delivers regularly in Italy and Europe.
I have tried pinging port 25 on these domains, and they all respond;
Googled about it, found something about MTU path setting in the kernel, but it seems to be regular.

DOES anybody have ANY idea about this?? :

I will appreciate anyone that could give a hint, clients are upset about not beeing able to send to their chinese partners...

P.S. I already tried to contact the administrators of such domains (through whois database), but haven't received an answer yet.

[jholder]

Hi Tommy-
Have you had any luck with this?

Normally, I'd say that it seems to be a problem on their end, but it looks like this is happening alot.

perhaps a restart of the server will help.

[moerlien]

This is likely because of the 'The Great China Firewall' that has been causing email problems this week. You can search the CNN website for the relevant news article.

[tommy]

Hehehe moerlien, then it seems I was part of the news somehow!
Yes, it is a problem on their end; although there are still some deferred email hanging around drinking beer in the deferred queue, they know eventually they will get delivered (semi drunk).

Administrators from .cn domains did not respond to me (some have exceeded quota!), so I had to wait anyway.

jholder, thanks for the response - always caring, aint you
I restarted all services when all this happened, but of course there was nothing wrong with zimbra.
I'm very happy with Zimbra; I really hope the message delivery notification gets implemented soon!

All's well, thx everyone!