SOLVED ZFS_WARNING: Unable to create ZVOL pool0/iSCSI (error=16)

[GarFin]

Hi, running 9.10.1 on i7 with 16GB RAM , 6 x 3T WD Red's in raidz2

So, i was cleaning up an old iSCSI filesystem, when NAS locked up.
on reboot , NAS would just freeze. A fresh build from USB fixes that, but when i try and import pool0 it keeps tripping up.

zpool import -fo readonly=on pool0 (from console as root) gives the following..
ZFS_WARNING: Unable to create ZVOL pool0/iSCSI (error=16)

i dont really need it to create it, as that is what i was trying to get rid of. However there is other data (ZVOLs) under pool0 that i DO wish to retain, so i cant simply scrub pool0


HELP !! please.

 

[mav@]

You may set vfs.zfs.vol.mode tunable to 0 to not expose zvols at all and avoid those error messages, but I'm afraid it may only be a cosmetics.

 

[GarFin]

I'm not sure either if set vfs.zfs.vol.mode=0 will help because there are other zvols on pool0 i still need to access, if only to back them up elsewhere before i scrub and start pool0 from fresh.

Nas is currently 12 hours into running
# zdb -AAA -e -p /dev -F pool0
with 86 hours to go.

(i might let that finish, first, before i try anything else.)



*update*
Still progressing @ 46MB/s 44Hrs to go..

*update*
Doh! rookie mistake.. command died with only a handful of hours left to complete due to lack of swap , checked, didn't have any swap set.


Take2 .. Plenty of swap this time.

 

[GarFin]

*update*
Nothing i tried (running latter versions of FreeBSD) has worked, I've had to resort to going back to FreeBSD 9.1 so i can forcibly mount the volume without running out system RAM ( on FreeBSD 9.2 onwards, all my RAM would eventually be consumed by 'Wired' memory. ) data copies to elsewhere, now underway. Cheers.