Are you using the MySQL backend for rsyslog, or is cacti just parsing the logs?
Nope, i'm using the mysql backend.
If you want to get fancy, you can enable remote syslog sending on your MD's, listening on the core, and then you can run a central syslog server on the core.
Other devices in my network (like the switch, routers, power sensors...) are already sending their logs to the linuxMCE machine. This is/was the whole meaning of using linuxmce.That it won't only control my infrastructure, but also monitor it. And warn me about problems. fe i receive almost daily a mail from cacti that my power consumption hits 4KW. So then i know that my girlfriend is preparing some food for me...

You might want to put up a wiki page ... so that others can follow in your footsteps...
You're right, but you know, written documentation is so hard. Trying to recall each step you made...
But i promise, next week, i'll install a new linuxmce server, and redo the whole installation of cacti with all plugins/steps...