Curtis:
> Ok, we have confirmed that the postfix/smtp threads are not just
> hanging... after several minutes of logging nothing, each thread exits
> with a log entries that looks like this (real host names/IPs masked with
> ---):
>
> May 9 13:36:50 --- postfix/smtp[1114]: 3b3cyK07Bzz41vV6: conversation
> with ---.---.com[---.---.---.---] timed out while sending message body
> May 9 13:36:51 --- postfix/smtp[1114]: 3b3cyK07Bzz41vV6: enabling PIX
> workarounds: disable_esmtp delay_dotcrlf for ---.---.com[---.---.---.---]:25
> May 9 13:46:53 --- postfix/smtp[1114]: 3b3cyK07Bzz41vV6:
> to=<---@---.com>, relay=---.---.com[---.---.---.---]:25, delay=349260,
> delays=348054/0.01/604/602, dsn=4.4.2, status=deferred (conversation
> with ---.---.com[---.---.---.---] timed out while sending message body)
Your outbound SMTP connections are timing out, because the receiving
end runs a PIX/ASA "security" "firewall".
These devices have a long history of breaking SMTP and that is why
Postfix turns on PIX workarounds as logged above.
> So, if qmgr is still running, then my question remains the same... since
> the active queue is growing what are possible reasons why new smtp
> threads would not be spawning until every last active thread gives up on
> this non-responsive mail server?
See the first example in my first reply: all mail is sent to the
deferred queue.
$ grep 'status=deferred' /the/maillog/file
and learn to read Postfix logfiles.
Wietse
