Matias - ZFS HELP!

Hi there, this is a question for Allan aka The Wizard of oZFS, and probably not very interesting for the show.

I am not really sure whether this is appropriate or not, so please do not hesitate to not answer, but pretty please just let me know you won't :D

I have just f****d up my laptop's root pool. I have a backup of the important data though there are a quite a few scripts and config files it would save me time to get back, but mostly I would like to see whether things can be mended and learn. Though I guess metadata is easier corrupted than mended.

I was bothered by the name of my root pool [sys] that bit me in the *ss a couple of times as well as by the base dataset for my BEs [BOOT] as it was not standard and, though unlikely, might be the reason why TrueOS was not recognizing my BEs on installation.

So I booted into mfsBSD 10.3 and did the following

# zpool import -R /mnt sys tank
# zfs rename tank/BOOT tank/ROOT
# zpool get bootfs
# zfs list
* both showed my datasets mountpoints and pool bootfs had picked the changes nicely
* I edited the value of the bootfs in /boot/loader.conf
# zpool export
# zpool import tank
# shutdown -h now

Rebooting seemed to go well, even up to mounting the datasets but though installed apps were failing they were at least being recognized (ezjail, bsdstats, cups etc...)

I rebooted into mfsBSD and tried to go back on my changes

# zpool import -R /mnt tank sys

there the system told me there were about 2 seconds of changes lost irretrievably but I should be ok with a `zpool import -F tank` which I did, not thinking quite right anymore, as I should at least have specified an altroot.

Anyway when I try to import tank (or by pool id) I am now getting about 15 `Solaris: WARNING: can't open objset xxx, error 5`
ZFS filesystem is version 5, pool version 5000
`zpool status` returns no error, state online (a fat lot of good it does me, lol)

I have seen a few things online I might try, but I am not doing anything until I receive on Wednesday an exact copy of this HDD and byte-copy everything to it. A few questions:

- should I use dd for that or do you have any other suggestion?
- any suggestion as to what I should try to do?
- any idea/comment on where/why I f*****d up?

As I most definitely will not be adding a plain vanilla FreeBSD 11.0-RELEASE and a TrueOS BEs to my now dead laptop this week-end, I might just get myself Pan Mastery tonight, to keep my mind away from my lost daaaaaaaata.


All the best,

Matías