PVFS fault tolerence ?

[Ben Ransom]

I see that PVFS stripes data, but it seems there is no fault 
tolerance.  That is, a node goes down, and your data is not available.  So, 
although IDE drives are pretty reliable, the chance of data loss from a 
PVFS system is essentially the chance of a single node (disk) going down 
times the number of nodes in the PVFS file space.  Not so good.  So, yeah, 
I buy a large capacity tape drive.  But even then, do I have to look at 
restoring the *entire* PVFS volume, which could be very large (say 20 nodes 
times 30gb) just for loosing one node?  Odds are,  losing a disk is "when", 
not "if".

-Ben Ransom
  UC Davis