on 22.
You can forward the database-access through an SSH-tunnel.
additionally this system must be 24/7 and setting up HA setups for postgresql is tricky (i've done it twice before).
Perhaps you should look at FirebirdSQL it is suitable for 24/7 without tricks.
so it's already a
single point of failure - i simply don't want to ADD a point of failure.
You still have two points of failiure: a failiure of the NFS-Server itself and an stale-NFS-lock that might also tear down the system while the NFS-Server itself is still ok.
Elmar
