Dovecot and MySQL aborted connections.

[Reio Remma]

On 28/10/2019 11:28, Gerald Galster via dovecot wrote:
> Hi,
>
>> Is anyone else using Dovecot (2.3.8) with MySQL (5.7) seeing a lot of these in MySQL logs?
>>
>> 2019-10-28T11:08:20.384428+02:00 58378 [Note] Aborted connection 58378 to db: 'vmail' user: 'vmail' host: 'localhost' (Got an error reading communication packets)
>> 2019-10-28T11:10:09.821171+02:00 58420 [Note] Aborted connection 58420 to db: 'vmail' user: 'vmail' host: 'localhost' (Got an error reading communication packets)
>> 2019-10-28T11:11:26.170015+02:00 58441 [Note] Aborted connection 58441 to db: 'vmail' user: 'vmail' host: 'localhost' (Got an error reading communication packets)
>> 2019-10-28T11:13:14.091426+02:00 58459 [Note] Aborted connection 58459 to db: 'vmail' user: 'vmail' host: 'localhost' (Got an error reading communication packets)
>>
>> They've plagued my logs for as long as I can remember. Is Dovecot not closing connections to the database properly or something similar?
> is it possible MySQL closed inactive connections?
>
> SHOW VARIABLES LIKE '%timeout%';
>
> mysqlx_wait_timeout = 3600
> wait_timeout = 3600
> mysqlx_interactive_timeout = 3600
> interactive_timeout = 3600
>
> Gerald

Variable_name    Value
connect_timeout    10
interactive_timeout    28800
lock_wait_timeout    31536000
net_read_timeout    30
net_write_timeout    60
wait_timeout    28800

That sounds plausible.  I wonder how to solve it though. :) I don't get 
any such notices from OpenSMPTD using the same database.