2012-06-16 19:13, Scott Aitken wrote:
Given I am working with images, it's hard to put just anything "in place" of
lofi/2. ZFS scans all of the files in the directory for ZFS labels, so just
replacing lofi/2 with an empty file (for example) just means ZFS skips it,
which is the same result as deleting lofi/2 altogether. I did this, but to
no avail. ZFS complains about having insufficient replicas.
I've seen your post that a scrub doesn't start.
Did you try replacing the faulted device with an empty one after
the zpool import - i.e. with "zpool replace lofi/2 lofi/6"?
Also, maybe I missed - did you "zdb -l" your pool components
(the 5 lofi devices) to inspect and compare their ZFS labels?
There should be 4 per device, including the list of device
GUIDs for this TLVDEV and a "last known up-to-date TXG number"
for this disk, and you can see if they differ a lot as you
suspect, or if they don't.
When crafting an empty replacement lofi device, you can also
try to clone or forge a ZFS label for that disk, by dd'ing
the labels from lofi/2 to new empty lofi/6. There are 4 labels
each sized 256KB, two at the head of the drive (0..512KB) and
two at the very end (SZ-512KB..SZ).
If you haven't browsed the "zfs on-disk spec", it may be also
helpful (though outdated in regard to current features):
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