FUD about CGD and GBDE

Bernd Walter ticso at cicely12.cicely.de
Thu Mar 3 12:05:06 GMT 2005


On Thu, Mar 03, 2005 at 01:30:15AM +0100, Poul-Henning Kamp wrote:
> In message <20050302162928.0916237012 at arioch.imrryr.org>, Roland Dowdeswell wri
> tes:
> 
> >Let's discuss a simple example and see how it works.  Let's walk
> >through a user login, with /etc/passwd on GBDE and the filesystem
> >mounted with mtime.
> 
> These days, on the majority of low cost disks used in enduser
> configurations you risk looking an entire track if the disk were
> writing when you pulled power.  (People complain about this, but
> doesn't seem to be willing to pay to avoid it.)

No matter what disk you take - writes never have been atomic.
The major difference I see is that you get a read error back in
the disk failure case, while such a crypto failure produces more or
less random data without any error.
Mounting unclean filesystems rw for bg_fsck can be considered
dangerous with such unexpected data corruption.
And how would you know that a restore from backup is required for
a damaged file?

-- 
B.Walter                   BWCT                http://www.bwct.de
bernd at bwct.de                                  info at bwct.de



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