Mailcow-dockerized: HUGE Redis memory bug

[Knight1]

Relates to https://github.com/mailcow/mailcow-dockerized/issues/366

I always monitor my server which caused some major problems here and there. Redis was always reporting out of memory while logging in after some time. Restart fixed it for some time.

My Redis was running with used_memory_human:1.23G now I drooped it to used_memory_human:26.08M

The problem was found with redis-cli --bigkeys

[88.72%] Biggest list found so far 'DOVECOT_MAILLOG' with 1555499 items
Biggest list found 'POSTFIX_MAILLOG' has 2283723 items

I tracked it down to the roots.
This is the Dovecot container.

root@development:/etc/syslog-ng# su vmail
$ echo "test" > /dev/stdout
sh: 1: cannot create /dev/stdout: Permission denied

We execute the cronjob with logging to /dev/stdout but for 3 crons the user vmails does not have the permission to do so.
https://github.com/mailcow/mailcow-dockerized/blob/master/data/Dockerfiles/dovecot/Dockerfile#L94

@ntimo has the same problem while executing

docker exec -it mailcowdockerized_redis-mailcow_1_* redis-cli monitor | grep LTRIM

It should output 5 Lines every minute.

Solution is to remove the lines after the .sh, to use root, or another solution.

BUT: There are lines in most containers so that the container is doing it themself but it isn't.

Cheers
Tobias

[andryyy]

I already fixed it in the current image for managed mailcows, but merged not yet to this repo. :-( Enotime.

There are 3 crons reporting to dev/stdout, but only 2 are run by vmail.

I added a tty to dovecot-mailcow and added vmail to tty.

Thanks for reporting it. :-) I will hurry.

[andryyy]

Pushed a slightly different script now. But I promised I tested it... :-P