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Issue Setting the default_client_limit value for dovecot by Plesk as specified by the instructions

andreios

Regular Pleskian
When using Plesk to setup maximum number of connections, under mail server settings (in my case 1024), the client_limit setting is not adjusted as intended.
I found this support article that talks about this problem.
In this article it is suggested to increase default_client_limit to solve the problem.
However, the dovecot settings depend on Plesk and will disappear after an update.

I therefore suggest to let Plesk do the setting by calculating the setting as follows.
This is the warning that doveconf gives me:
Code:
doveconf: Warning: service auth { client_limit=1000 } is lower than required under max. load (2248). Counted for protocol services with service_count != 1: service managesieve-login {
process_limit=100 } + service pop3-login { process_limit=1024 } + service imap-urlauth-login { process_limit=100 } + service imap-login { process_limit=1024 }
doveconf: Warning: service anvil { client_limit=1000 } is lower than required under max. load (2251). Counted with: service managesieve-login { process_limit=100 } + service pop3-login { process_limit=1024 } + service imap-urlauth-login { process_limit=100 } + service imap-login { process_limit=1024 } + service auth { process_limit=1 }
This shows exactly how the value is calculated. If I insert the larger of the two calculated values into dovecot.conf, the message disappears.
Code:
default_client_limit = 2251

Here are the dovecot directions for "anvil" and "auth" in the docs.
 
That is strange as the files in /etc/dovecot/conf.d should not be overwritten on updates.
 
All files in my /etc/dovecot/*/* have this banner
# PLEASE DON'T EDIT ANYTHING IN THIS FILE! ANY CHANGES WILL BE LOST ON UPGRADE.
or this
#DO NOT MODIFY THIS FILE BECAUSE IT WAS GENERATED AUTOMATICALLY,
#SO ALL YOUR CHANGES WILL BE LOST THE NEXT TIME THE FILE IS GENERATED.

Only exception:
11-plesk-security-ssl.conf and *.pem

The files that are manged by setting max connections on the Plesk GUI are
conf.d/92-plesk-service-imap.conf
conf.d/92-plesk-service-imap-login.conf
conf.d/92-plesk-service-pop.conf
conf.d/92-plesk-service-pop-login.conf

Anyway I guess in this issue it would be best practice to let Plesk manage default_client_limit, as it seems to manage everything in dovecot one way or another. .
 
I must admit that I've been ignoring this and put my own config into the files anyway. The only situation where this ever needed a manual intervention was on the centos2alma upgrade when Dovecot was completely reinstalled. But many years before the configs were never changed.
 
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