zfs import from old TXG

[Chris Ross]

> On Aug 23, 2017, at 14:31, Volodymyr Kostyrko <arcade at b1t.name> wrote:
>>> That's -T, it was intentionally left undocumented.
>>> 
>>> /usr/src/cddl/contrib/opensolaris/cmd/zpool/zpool_main.c /starting txg
>> 
>>  Looking back at this, and trying to recover some data without multi-day clean/restore cycles.  I want to import my pool to an earlier txg.  I used zfs history to log the actions, and am trying to use “zpool import -N [-F] -T 7428 tank”.  With or without a -F argument, I get:
>> 
>> cannot import 'tank': one or more devices is currently unavailable
>> 
>>  However, zpool import shows all of its devices ONLINE, and I only exported it a short while ago.  Is there something I’m missing that I can provide to proceed with effectively importing an earlier state of this pool?
> 
> Available transactions can be listed with:
> 
> zdb -ul <device>
> 
> I can't remember how long it takes to overwrite old transactions but if the pool was imported more then a few hours after the disk was added older transactions would already be overwritten...
> 
> PS: If not minutes.

  It was imported, though not mounted, for a few minutes during which time I broke something I’m trying to recover, and a few minutes after until I exported it and started evaluating whether it was recoverable.

  Using zdb -ul, I see no tag’s around where I was aiming (7428), but I do see three in the 7300’s.  But, trying “zpool import -N -T 7375 tank” produces the same error.  As with the other two txg’s (7378, 7381) I saw.

  Any other ideas, since it looks like “available transaction” isn’t my [only] problem?

          - Chris


-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 801 bytes
Desc: Message signed with OpenPGP
URL: <http://lists.freebsd.org/pipermail/freebsd-fs/attachments/20170823/255f0ff5/attachment.sig>