I'm having a hard time understanding how logging works on linux.
Since the inclusion of systemd, it seems a bit easier, but I still have a couple of concepts that still can't fully understand.
Given a system with journalctl, I want to send some log messages to a remote host. For this purpose, I installed rsyslog and configured freeradius so it outputs its logs to local3, and then configured rsyslog to forward those messages under local3 to the remote syslog server. Now, are the system logs shared between rsyslog and journalctl? Can this cause a conflict of any kind?
Aside from this: Who controls what is being ritten to /var/log/messages? and how can a certain app output their logs to this file? Is it managed by rsyslog? By systemd?
If anyone can help me understand the whole linux logging service, it would be nice.