The problem is this yahoo and yahoo alone fails to make connections, the problem is random,most emails come through just fine, the specific failures are not repeatable. But an parker of ours uses yahoo business serves for their email, they are getting timeout bounces on 1 in 10 emails sent to us.
That is the best description that I have for this issue. As for the verboseness I added this debug_peer_list = yahoo.com to main.cf. It fails with this off as well. If its a local disk race condition why only yahoo and not any other domain. If its DNS issue, why yahoo and no other domain? I had thought that its a firewall mucking the TCP packets, no avail. So I am probably missing something in either my setup or in the log file hence why its included. Thanks, eric eric smith senior network administrator http://www.techsoft3d.com email: e...@techsoft3d.com skype: eric_ae_smith phone: 510-333-1729 On 7/21/11 11:46 AM, "Victor Duchovni" <victor.ducho...@morganstanley.com> wrote: >On Thu, Jul 21, 2011 at 06:39:58PM +0000, Eric Smith wrote: > >> Hi All, >> >> Here is a strange issue, incoming mail for yahoo fails roughly every >>10th time. Also this is (reportedly) only happening to yahoo emails, all >>other email domains come through just fine. >> >> The setup is on ubuntu 10.4 LTS with the standard packages, postfix, >>clamav, amavis and spamassassin. >> >> I have tried many different solutions, TCP_window size is set to 64, >>300 smtp process's is the limit, the system is not being overloaded. I >>also have worked with Sonicwall to make sure that the TCP packets are >>not getting munged. >> >> Any thoughts? > >You have failed to describe the problem. > >> Failed connection: >> >> Jul 21 09:15:55 loki postfix/smtpd[23510]: connect from >>nm1-vm0.bullet.mail.ne1.yahoo.com[98.138.91.74] >> Jul 21 09:15:55 loki postfix/smtpd[23510]: match_hostname: >>nm1-vm0.bullet.mail.ne1.yahoo.com ~? 192.168.1.0/24 > >Why is verbose logging enabled, turn it off. > >> Jul 21 09:15:55 loki postfix/smtpd[23510]: > >>nm1-vm0.bullet.mail.ne1.yahoo.com[98.138.91.74]: 220 mail.techsoft3d.com >>ESMTP Postfix >> Jul 21 09:15:55 loki postfix/smtpd[23510]: smtp_get: EOF > >Yahoo dropped the connection, probably before you even accepted it. With >verbose logging slowing down your server, it may take too long from TCP >3-way handshake until a Postfix smtpd is ready to process it. > >> Jul 21 09:15:55 loki postfix/smtpd[23510]: lost connection after >>CONNECT from nm1-vm0.bullet.mail.ne1.yahoo.com[98.138.91.74] >> Jul 21 09:15:55 loki postfix/smtpd[23510]: disconnect from >>nm1-vm0.bullet.mail.ne1.yahoo.com[98.138.91.74] > >First turn off verbose logging. Then make sure your syslog is not >doing synchronous writes to disk for every log message. Then see whether >you still have a problem. > >Yahoo is timing out you server. Perhaps your DNS is also slow. > >-- > Viktor.
