Replacing Drive with SSD
Brandon J. Wandersee
brandon.wandersee at gmail.com
Fri Aug 28 17:37:47 UTC 2015
Matt Smith writes:
> I've heard a rumour that you should never use dd with SSD drives because
> of the wear levelling stuff. Apparently SSDs automatically make sure
> that data is sent to unused flash cells so that all the cells wear
> evenly, but if you use dd on them it makes them think that every single
> cell is in use which screws this up?
I've read the same thing before, but I can't imagine it would really be
a problem if it's the first thing you do with a new disk (and the only
time you do it). Personally, though, I would just avoid using dd.
If you're making a 1:1 clone of a system--if you're copying the same
partition scheme to a newly purchased disk of the exact same make and
model--then dd is fine, but since dd can't account for partition size or
alignment, differences in block/cylinder count, filesystem settings (you
should activate TRIM and eschew SU+J *before* copying a large amount of
data over) and what-not, it's best to just create new partitions and
filesystems and use the dump/restore method.
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:: Brandon Wandersee ::
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