Resolved smtpd_timeout set too high

[obendev]

User name: lkdvc

TITLE

smtpd_timeout set too high

PRODUCT, VERSION, OPERATING SYSTEM, ARCHITECTURE

Plesk Obsidian v18.0.28_build1800200720.10 os_Ubuntu 18.04

PROBLEM DESCRIPTION

As @mr-wolf said in his post (Issue - smtpd_timeout = 3600s, why is Plesk so anxious to make that entry in main.cf???), the postfix configuration smtpd_timeout is unnecessarily high or there’s no real reason why it should be set this high.
I'd like to quote @mr-wolf here:

The Internet was already a bad place with all those spammers 10 years ago, but it only got worse.
A timeout of an hour is way too long nowadays to let them hog your resources.

And this is true.

The post configuration manual (Postfix Configuration Parameters) states that the default value is 300 seconds and that really should be by far enough.

STEPS TO REPRODUCE

Check /etc/postfix/main.cf

ACTUAL RESULT

It is set to 3600s (≙ 1 hour)

EXPECTED RESULT

The default value of 300s (≙ 5 minutes) should be high enough.

ANY ADDITIONAL INFORMATION

Postfix Stress-Dependent Configuration

Postfix Performance Tuning

Amavis point of view

https://www.ijs.si/software/amavisd/release-notes.txt

https://web.archive.org/web/20200729094849/https://www.ijs.si/software/amavisd/release-notes.txt
amavisd-new-2.4.0 release notes, April 3, 2006

introduced new configuration variable $smtpd_timeout (default 8*60 seconds)
which controls the amount of time we are willing to wait for slow/idle client
during incoming SMTP session before disconnecting a session. Previously the
$child_timeout was covering complete elapsed time, both our processing and
waiting for client, now the $child_timeout only still limits our processing,
and $smtpd_timeout only limits waiting time. With Postfix after-queue setup
the $smtpd_timeout should be higher than Postfix setting max_idle (default
100s). Some other setups (like a pre-queue setup) may demand substantially
higher $smtpd_timeout values; inflexibility pointed out by Martin Schmitt;

YOUR EXPECTATIONS FROM PLESK SERVICE TEAM

Confirm bug

 

[IgorG]

Thank you.
After investigating original reasons for such customization in Plesk developers filed PPPM-12236 to address this issue.

 

[IgorG]

Fixed in Plesk 18.0.32:

Plesk no longer specifies excessively large smtpd_proxy_timeout and smtpd_timeout values in Postfix configuration files during Plesk installation or whenever the plesk repair mail command is run. (PPPM-12236)

Change Log for Plesk Obsidian

Find out about changes, additions and updates to Plesk Obsidian on an iteration to iteration basis.

docs.plesk.com