Hello fellow BOFH,
I also went by that title in a previous life ;)
2012-05-16 21:58, bofh wrote:
Err, why go to all that trouble? Replace one disk per pool. Wait for
resilver to finish. Replace next disk. Once all/enough disks have
been replaced, turn on autoexpand, and you're done.
As I wrote in the start of the thread, the original
pool had 45 250Gb disks laid out as raidz1.
This level of redundancy is too small for big disks -
i.e. the recent resilver of a 250Gb disk, when it
did finally succeed, took 15 hours. It seems likely
that a 3Tb disk would take at least 12x time, about
a week (likely more) that a raidz1 dataset would
remain unprotected in the face of another failure.
So an in-place upgrade by autoexpansion would require:
1) keep the raidz1 layout which is unsafe;
2) upgrade all 45 disks which is too much storage
for current needs, and a big cost paid for no
benefit to the buyer.
So this method was ruled out for this situation.
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