sending with large attachments times out, but message is sent anyway

[bkc]

We are running zcs-6.0.9_GA_2686.UBUNTU10_64.20101115235226 on Ubuntu 10.04 w/ split dns (dnscache + tinydns), for quite some time and haven't had any issues.

last week the web interface began acting strangely when sending messages with large attachments to external users. Oddly I've been told that the desktop version does not exhibit this problem, but I have not tested that myself.

Using fiddler I've tracked this down to this browser post:

POST /service/soap/SendMsgRequest

The web request times out after exactly 4 minutes

ServerConnected:	10:19:21.170
FiddlerBeginRequest:	10:19:21.217
ServerGotRequest:	10:19:21.217
ServerBeginResponse:	10:23:22.099
ServerDoneResponse:	10:23:22.100
ClientBeginResponse:	10:23:22.100
ClientDoneResponse:	10:23:22.101

Overall Elapsed:	00:04:00.8837891

this exception is recorded in mailbox.log

2011-10-04 10:23:24,548 INFO  [btpool0-210://zimbra.c.ca/service/soap/SendMsgRequest] [name=bkc@c.ca;mid=10;ip=192.168.1.149;ua=ZimbraWebClient - FF3.0 (Win)/6.0.9_GA_2686;] SoapEngine - handler exception
com.zimbra.common.service.ServiceException: system failure: Unable to send message
		ExceptionId:btpool0-210://zimbra.c.ca/service/soap/SendMsgRequest:1317738204547:1355a48a4fe8e32a
		Code:service.FAILURE
			at com.zimbra.common.service.ServiceException.FAILURE(ServiceException.java:248)
			at com.zimbra.cs.mailbox.MailSender.sendMimeMessage(MailSender.java:477)
			at com.zimbra.cs.mailbox.MailSender.sendMimeMessage(MailSender.java:309)
			at com.zimbra.cs.mailbox.MailSender.sendMimeMessage(MailSender.java:266)

...
Caused by: com.zimbra.cs.mailbox.MailSender$SafeMessagingException: Exception reading response; chained exception is:
			java.net.SocketTimeoutException: Read timed out
			at com.sun.mail.smtp.SMTPTransport.readServerResponse(SMTPTransport.java:1764)
			at com.sun.mail.smtp.SMTPTransport.close(SMTPTransport.java:823)
			at com.zimbra.cs.mailbox.MailSender.sendMessageToHost(MailSender.java:785)
			at com.zimbra.cs.mailbox.MailSender.sendMessage(MailSender.java:702)
			at com.zimbra.cs.mailbox.MailSender.sendMimeMessage(MailSender.java:412)

oddly, the message *is* sent to the external recipient with the attachment.
But the message also stays in the drafts folder.

when sending to a local recipient, the message is not sent after the 4 minute timeout.

During the 4 minute period, load on the server is very low, nothing is happening.

I suppose this is probably some kind of dns timeout issue. I have checked dns carefully and I believe it is setup correctly.

I cannot find a 240 second timeout in any config file. The delay occurs for all external recipients receiving large messages, though I have only tested one recipient to calculate the 'exact' 4 minute timeout.

The message that is received (after the 4 minute delay) has these headers:

Received: from zimbra.x.com ([24.97.99.250]) by na3sys009amx212.postini.com ([74.125.148.11]) with SMTP;
	Tue, 04 Oct 2011 14:25:25 GMT
Received: from localhost (localhost.localdomain [127.0.0.1])
	by zimbra.x.com (Postfix) with ESMTP id A9007426B2
	for <bkc@murkworks.com>; Tue,  4 Oct 2011 10:25:23 -0400 (EDT)
X-Virus-Scanned: amavisd-new at zimbra.x.com
Received: from zimbra.x.com ([127.0.0.1])
	by localhost (zimbra.x.com [127.0.0.1]) (amavisd-new, port 10024)
	with ESMTP id KaY4+uehwz7D for <bkc@z.com>;
	Tue,  4 Oct 2011 10:25:23 -0400 (EDT)
Received: from zimbra.x.com (zimbra.x.com [192.168.1.208])
	by zimbra.x.com (Postfix) with ESMTP id 32F854251C
	for <bkc@z.com>; Tue,  4 Oct 2011 10:19:24 -0400 (EDT)

(host names altered above)

related lines from mailbox.log

2011-10-04 10:19:23,670 INFO  [btpool0-210://zimbra.c.ca/service/soap/SendMsgRequest] [name=bkc@c.ca;mid=10;ip=192.168.1.149;ua=ZimbraWebClient - FF3.0 (Win)/6.0.9_GA_2686;] soap - SendMsgRequest
2011-10-04 10:19:24,128 INFO  [btpool0-210://zimbra.c.ca/service/soap/SendMsgRequest] [name=bkc@c.ca;mid=10;ip=192.168.1.149;ua=ZimbraWebClient - FF3.0 (Win)/6.0.9_GA_2686;] mailop - Adding Message: id=4
60, Message-ID=<494151752.368.1317737963671.JavaMail.root@zimbra>, parentId=-1, folderId=5, folderName=Sent.
2011-10-04 10:19:24,201 INFO  [btpool0-198://zimbra.c.ca/service/soap/NoOpRequest] [name=bkc@c.ca;mid=10;ip=192.168.1.149;ua=ZimbraWebClient - FF3.0 (Win)/6.0.9_GA_2686;] soap - NoOpRequest
2011-10-04 10:19:24,202 INFO  [btpool0-210://zimbra.c.ca/service/soap/SendMsgRequest] [name=bkc@c.ca;mid=10;ip=192.168.1.149;ua=ZimbraWebClient - FF3.0 (Win)/6.0.9_GA_2686;] smtp - Sending message to MTA
 at zimbra.x.com: Message-ID=<494151752.368.1317737963671.JavaMail.root@zimbra>, replyType=r
2011-10-04 10:19:24,748 INFO  [btpool0-196://zimbra.c.ca/service/soap/NoOpRequest] [name=bkc@c.ca;mid=10;ip=192.168.1.149;ua=ZimbraWebClient - FF3.0 (Win)/6.0.9_GA_2686;] soap - NoOpRequest
2011-10-04 10:19:55,899 INFO  [btpool0-196://zimbra.c.ca/service/soap/NoOpRequest] [name=bkc@c.ca;mid=10;ip=192.168.1.149;ua=ZimbraWebClient - FF3.0 (Win)/6.0.9_GA_2686;] soap - NoOpRequest	
2011-10-04 10:19:56,410 INFO  [btpool0-215://zimbra.c.ca/service/soap/NoOpRequest] [name=bkc@c.ca;mid=10;ip=192.168.1.149;ua=ZimbraWebClient - FF3.0 (Win)/6.0.9_GA_2686;] soap - NoOpRequest	
2011-10-04 10:23:24,433 INFO  [btpool0-210://zimbra.c.ca/service/soap/SendMsgRequest] [name=bkc@c.ca;mid=10;ip=192.168.1.149;ua=ZimbraWebClient - FF3.0 (Win)/6.0.9_GA_2686;] mailop - Deleting Message (id=460).
2011-10-04 10:23:24,547 INFO  [btpool0-215://zimbra.c.ca/service/soap/NoOpRequest] [name=bkc@c.ca;mid=10;ip=192.168.1.149;ua=ZimbraWebClient - FF3.0 (Win)/6.0.9_GA_2686;] soap - NoOpRequest
2011-10-04 10:23:24,548 INFO  [btpool0-210://zimbra.c.ca/service/soap/SendMsgRequest] [name=bkc@c.ca;mid=10;ip=192.168.1.149;ua=ZimbraWebClient - FF3.0 (Win)/6.0.9_GA_2686;] SoapEngine - handler exception

any ideas?

thanks

[bkc]

The person who told me that sending w/ large attachments works in zimbra desktop just said "no, it's not working". I thought they were wrong, and now we know.. it doesn't work using either the plain web interface or zimbra desktop.