Handbook RAID1 example
wblock at wonkity.com
Fri Mar 30 03:23:15 UTC 2012
On Tue, 27 Mar 2012, Warren Block wrote:
> Procedure tested on both 9.0-RELEASE and 8.2-RELEASE. It could stand more
And more testing does show a problem.
My tests were all using the smaller drive as the new drive (20G).
Create a mirror using that whole drive, copy the data from the 20G
allocated space on the original 200G drive.
But it doesn't work the other way around. Create a mirror of the full
larger drive, and the smaller drive cannot be inserted into it; it can't
mirror a 200G drive.
The procedure really ought to work with different-sized drives, because
that situation is expectable.
Telling the users that the disks must be identical is weak. It may
still fail because of the presence or absence of a label or other
metadata eating one or more sectors even if the drives are identical.
Now I'm considering labeling each disk, then using gnop(8) to create a
matching-sized device on each. This adds more complexity, and maybe the
thing to do is put the whole thing into a shell script.
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