On Thu, Feb 05, 2004 at 09:31:48AM +0700, Frank Rabitsch wrote: > guys, > > First of all thanks for all the great work you put into releasing the > monthly QMail LDAP patch. It saves me a lot of work because this patch > provides me a one stop solution for my QMail environment. > > I have a strange problem with QMQP. I'm running a QMail LDAP cluster in > three different countries. In two out of the three countries my users > are complaining of receiving a lot of double messages. > > Investigation of the log file learns me that the messages are indeed > send multiple times. The only difference is the qmail ID (946 and 1041) > and the time is slightly different on the receiving server. ID's are the > same on the sending server. > > Received: (qmail 946 invoked from network); 4 Feb 2004 03:05:05 -0000 > Received: from unknown ([10.1.0.7]) by mail.ph.magnusint.com > (qmail-ldap-1.03) with compressed QMQP; 4 Feb 2004 03:05:05 -0000 > Delivered-To: CLUSTERHOST mail.id.magnusint.com [EMAIL PROTECTED] > > Received: (qmail 1041 invoked from network); 4 Feb 2004 03:07:36 -0000 > Received: from unknown ([10.1.0.7]) by mail.ph.magnusint.com > (qmail-ldap-1.03) with compressed QMQP; 4 Feb 2004 03:07:36 -0000 > Delivered-To: CLUSTERHOST mail.id.magnusint.com [EMAIL PROTECTED] > > Next to that I see a number of error messages on the sending server: > > @400000004021a06822ddb66c delivery 842: deferral: > Unable_to_cluster-forward_message:_communication_with_mail_server_failed_(#4.4.2)./ > > @400000004020c29a27a0013c delivery 2761: deferral: > Unable_to_cluster-forward_message:_connection_to_mail_server_timed_out_(#4.4.1)./ > > At first I thought there was a version conflict between QMail > installations but over the weekend I installed the servers on exactly > the same QMail LDAP patch (20040101). I did a clean install with default > settings provided in the boot scripts. QMQP compression is enabled on > the servers. > > My suspicion is that the communication channel is somehow interrupted > before the receiving party can confirm correct reception of the email > which causes the sending party to resend the email. The strange thing is > that this only happens in two out of three servers. On the 3rd server I > never receive any double messages. > > Is this problem connection related? If yes, is there a setting to change > so that QMQP is less sensitive to connection errors? SMTP doesn't show > the above mentioned problems on the same connection so I assume that > QMQP should have the same behavior. > > Anything else that went wrong in my setup? Your feedback is appreciated. >
I see two possibilities: 1. there is a problem with compression. I have a setup that uses compressed qmqp quite excessively without a problem. 2. timeouts. qmqp is known to have to radical timeouts. qmqpc has a 10 sec connect timeout and a 60 sec read timeout qmqpd a generic 3600 sec timeout. The 10 sec timeout seems to be somewhat short but that would definitifly not cause double deliveries. The "connection_to_mail_server_timed_out" error is the 10 sec timer and my guess is, that all tcpserver slosts where full. The second error seems to be a read timeout just at the end of the transaction. Do you have a log of the qmail-qmqpd? -- :wq Claudio
