Hi Klug
Thanks for the warm welcome.
I knew i could receive a message saying: you´re stuck

Well, DRDB should be a choice, but we did not set /opt to a partition for itself. I think i cannot use drdb at folder level, is that correct? The system have a very simple partition scheme. a /, a /boot and a /var. /opt obviously ended up on / and i cannot drdb the root partition. This system is already in production.
I don´t know about GFS, checking now...
Thanks.