Bill Sommerfeld wrote:
On Wed, 2009-11-11 at 10:29 -0800, Darren J Moffat wrote:
Joerg Moellenkamp wrote:
Hi,
Well ... i think Darren should implement this as a part of
zfs-crypto. Secure Delete on SSD looks like quite challenge, when wear
leveling and bad block relocation kicks in ;)
No I won't be doing that as part of the zfs-crypto project. As I said
some jurisdictions are happy that if the data is encrypted then
overwrite of the blocks isn't required. For those that aren't use
dd(1M) or format(1M) may be sufficient - if that isn't then nothing
short of physical destruction is likely good enough.
note that "eradication" via overwrite makes no sense if the underlying
storage uses copy-on-write, because there's no guarantee that the newly
written block actually will overlay the freed block.
Which is why this has to be a ZFS feature rather than something link GNU
shred(1) which runs in userland.
IMHO the sweet spot here may be to overwrite once with zeros (allowing
the block to be compressed out of existance if the underlying storage is
a compressed zvol or equivalent) or to use the TRIM command.
Exactly.
--
Darren J Moffat
_______________________________________________
zfs-discuss mailing list
zfs-discuss@opensolaris.org
http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
