[Linux-cluster] How do you HA your storage?

[urgrue]

I'm struggling to find the best way to deal with SAN failover.
By this I mean the common scenario where you have SAN-based mirroring.
It's pretty easy with host-based mirroring (md, DRBD, LVM, etc) but how
can you minimize the impact and manual effort to recover from losing a
LUN, and needing to somehow get your system to realize the data is now
on a different LUN (the now-active mirror)?