I have been having this same problem except on a separate partition ( not root).
I was able to get past the "failed to mount" issue by running modprobe but then
I get
● zfs-share.service - ZFS file system shares
Loaded: loaded (/lib/systemd/system/zfs-share.service; enabled; vendor
preset: enabled)
Active: failed (Result: exit-code) since Mon 2019-08-05 18:43:16 EDT; 9ms ago
Docs: man:zfs(8)
Process: 27806 ExecStartPre=/bin/rm -f /etc/dfs/sharetab (code=exited,
status=0/SUCCESS)
Process: 27807 ExecStart=/sbin/zfs share -a (code=exited, status=1/FAILURE)
Main PID: 27807 (code=exited, status=1/FAILURE)
Aug 05 18:43:16 X470-AORUS-ULTRA systemd[1]: Starting ZFS file system shares...
Aug 05 18:43:16 X470-AORUS-ULTRA zfs[27807]: cannot share 'Media': share(1M)
failed
Aug 05 18:43:16 X470-AORUS-ULTRA systemd[1]: zfs-share.service: Main process
exited, code=exited, status=1/FAILURE
Aug 05 18:43:16 X470-AORUS-ULTRA systemd[1]: zfs-share.service: Failed with
result 'exit-code'.
Aug 05 18:43:16 X470-AORUS-ULTRA systemd[1]: Failed to start ZFS file system
shares.
dpkg: error processing package zfsutils-linux (--configure):
installed zfsutils-linux package post-installation script subprocess returned
error exit status 1
Setting up gcc-8-base:i386 (8.3.0-6) ...
Setting up libgpg-error-l10n (1.35-1) ...
dpkg: dependency problems prevent configuration of zfs-zed:
zfs-zed depends on zfsutils-linux (>= 0.7.12-2+deb10u1); however:
Package zfsutils-linux is not configured yet.
dpkg: error processing package zfs-zed (--configure):
dependency problems - leaving unconfigured
I assumed it was my fault, something stupid I did, untill yesterday after a
fresh install of buster, using ext4 for my root partition.
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