I have a Ubuntu 17.10 powered server with a separate root disk and one ZFS pool composed of three hard disks. Each time I start the server after it was properly powered off, the zpool does not automatically appear. However, if I reboot the server after its first boot, the ZFS pool gets automatically mounted and appears.
The setup is as follows:
$ sudo zpool status NAME SIZE ALLOC FREE EXPANDSZ FRAG CAP DEDUP HEALTH ALTROOT mydata 5.44T 2.88T 2.55T - 8% 53% 1.00x ONLINE - $ sudo zpool list pool: mydata state: ONLINE scan: scrub repaired 0 in 10h33m with 0 errors on Mon Apr 2 00:53:06 2018 config: NAME STATE READ WRITE CKSUM mydata ONLINE 0 0 0 raidz1-0 ONLINE 0 0 0 ata-SAMSUNG_HD204UI_S2H7J9AB809595 ONLINE 0 0 0 ata-SAMSUNG_HD204UI_S2H7J9JB808621 ONLINE 0 0 0 ata-SAMSUNG_HD204UI_S2H7J90B833202 ONLINE 0 0 0 errors: No known data errors
I've already tried to adjust
/etc/default/zfs and set the mount option, unfortunately without success.
$ cat /etc/default/zfs | grep MOUNT ZFS_MOUNT='yes' ZFS_UNMOUNT='yes' VERBOSE_MOUNT='no' DO_OVERLAY_MOUNTS='no' MOUNT_EXTRA_OPTIONS="" ZFS_INITRD_PRE_MOUNTROOT_SLEEP='0'
Of course, all packages are up to date including ZFS. The system partition is not on the ZFS pool but on a separate disk:
$ df -h Filesystem Size Used Avail Use% Mounted on udev 1.9G 0 1.9G 0% /dev tmpfs 393M 956K 392M 1% /run /dev/mapper/mm--server--vg-root 2.9G 2.7G 121M 96% / tmpfs 2.0G 0 2.0G 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 2.0G 0 2.0G 0% /sys/fs/cgroup /dev/sda1 472M 194M 254M 44% /boot
I have spent some time researching the issue but this appears to be the opposite to the more common problems in which the pool does not persist over the reboot -- whilst in this case the pool only appears if I reboot the server but not on the first boot after the server was powered off. My problem is reproducible.
Any pointers to what the issue could be are highly appreciated.