For the moment there's a lot of choices for setting up a Linux cluster.
For cluster manager: you can use Red Hat Cluster manager, Pacemaker or Veritas Cluster Server. The first one has the most momentum, the second one comes by default with RH subscriptions and the last one is very expensive and has a very good reputation ;-)
For storage: - You can replicate LUN's using software raid / md device - You can use the network using DRBD replication, which offers a bit more flexibility - You can use Veritas Storage Foundation technology to talk to your SANs replication technology.
Anyone has any recommandations or experience with these technologies?