After upgrading to 4.4.0-59 yesterday I realized today that my zfs partitions were gone! Googling a bit suggested that [http://pastebin.com/BPFj1Ewj ] zfs-native 0.6.5.7 did not like (as in: compile with) the -59 kernel.
Sure enough, zfs is missing from the -59 kernel (check last 2 lines):
% dkms status bbswitch, 0.7, 4.4.0-53-generic, x86_64: installed bbswitch, 0.7, 4.4.0-57-generic, x86_64: installed bbswitch, 0.7, 4.4.0-59-generic, x86_64: installed nvidia-340, 340.98, 4.4.0-53-generic, x86_64: installed nvidia-340, 340.98, 4.4.0-57-generic, x86_64: installed nvidia-340, 340.98, 4.4.0-59-generic, x86_64: installed spl, 0.6.5.7, 4.4.0-53-generic, x86_64: installed spl, 0.6.5.7, 4.4.0-57-generic, x86_64: installed spl, 0.6.5.7, 4.4.0-59-generic, x86_64: installed virtualbox, 4.3.36, 4.4.0-53-generic, x86_64: installed virtualbox, 4.3.36, 4.4.0-57-generic, x86_64: installed virtualbox, 4.3.36, 4.4.0-59-generic, x86_64: installed zfs, 0.6.5.7, 4.4.0-53-generic, x86_64: installed zfs, 0.6.5.7, 4.4.0-57-generic, x86_64: installed
Ok, what to do? Reboot under the previously known good kernel (-57)!
After rebooting, sure I can access my zpool, but my partitions are not mounted. To confuse matters even more,
zpool statussuggests I upgrade my pool:
% sudo zpool status pool: tank state: ONLINE status: Some supported features are not enabled on the pool. The pool can still be used, but some features are unavailable. action: Enable all features using 'zpool upgrade'. Once this is done, the pool may no longer be accessible by software that does not support the features. See zpool-features(5) for details. scan: none requested config: NAME STATE READ WRITE CKSUM tank ONLINE 0 0 0 mirror-0 ONLINE 0 0 0 ata-ST4000DM000-1F2168_S3014GKE-part4 ONLINE 0 0 0 ata-WDC_WD40PURX-64GVNY0_WD-WCC4E5UZUFFD-part4 ONLINE 0 0 0 errors: No known data errors
Dare I do that? Or, did something get messed up during the failed update to 4.4.0-59? I have installed zfs via
apt-get install ubuntu-zfsand do not feel brave enough to try to compile and install the zfs module myself. For now, I just want my zfs partitions back!
Update: I have posted the solution that worked below. It might be against askubuntu rules, but I wanted to have this info out as soon as possible if someone else were to run into the same problem.
secure boot
disabled in the BIOS? Do a modinfo and check thevermagic
value in the zfs kernel module and make sure it matches the new kernel version.upgrade
message is due to a new version of ZFS you are using (newer than the one your pool was created with). There is no need to update the pool, as long as you do not need the new features (and if you don't know what they are, you do not need them!). If you upgrade your pool, you will have problems in case of downgrading the ZFS version (aka "Fetaure Flags", see e.g. open-zfs.org/wiki/Feature_Flags)