How to get rid of server message "Core Dumps"

I’m always keen to have no error messages in logs.
like this one:
Coredumps will not be generated: kopano-server requires the fs.suid_dumpable sysctl to contain the value 2, not 0. See kopano-coredump(5) for details.

Very simple to be removed (

mkdir /opt/corefiles
chmod 0777 /opt/corefiles

Add the line below in /etc/security/limits.conf

  •           soft    core            unlimited

And create file /etc/sysctl.d/100-cores.conf with this content:
kernel.core_pattern = /opt/corefiles/core.%e.%t.%p
kernel.core_pipe_limit = 0
kernel.core_uses_pid = 0
fs.suid_dumpable = 2

Reboot - one line of error messages less :-)

The error is there for a reason - AFAICT your config file specifically asked for coredumps by way of “enable_coredumps = yes”. If you do not want them, drop the line from the cfg.