Yes, DRBD is the right choice for replication over ethernet.
Also, you can try Pacemaker (
http://www.clusterlabs.org/wiki/Main_Page) :
"Pacemaker achieves maximum availability for your cluster services by detecting and recovering from node and service-level failures. It achieves this by utilizing the messaging and membership capabilities provided by your preferred cluster infrastructure (currently either OpenAIS or Heartbeat), "
BR,
Stefan
