ZFS and block deduplication

[Edward Ned Harvey]

> From: Tom Metro [mailto:tmetro-blu-5a1Jt6qxUNc at public.gmane.org]
> 
> (Doesn't ZFS also employ overall file hashing to insure the integrity of
> a file? (Or is that the verification option you referred to?) If so,
> then that would likely thwart this attack vector.)

The data integrity hash is something much faster and weaker.  I forget
exactly what.  

If you enable dedup, I don't know if the sha256 is used instead of, or in
addition to the data integrity hash.