Set mountpoint=/ for your root dataset (for
compatibility, legacy also works, but is not recommended
for new installations):
zfs set mountpoint=/ pool/dataset
Either (a) set bootfs= on the pool to the dataset:
zpool set bootfs=pool/dataset pool
Or (b) append root=zfs:pool/dataset to your kernel
cmdline.
Re-generate your initrd and update it in your boot bundle
Encrypted datasets have keys loaded automatically or prompted
for.
If the root dataset contains children with mountpoint=s
of /etc, /bin, /lib*, or
/usr, they're mounted too.
For complete documentation, see dracut.zfs(7).
cmdline
root=
Root dataset is…
(empty)
the first bootfs= after
zpool import -aN
zfs:AUTO, zfs:, zfs
(as above, but overriding other autoselection methods)
ZFS=pool/dataset
pool/dataset
zfs:pool/dataset
(as above)
All +es are replaced with spaces (i.e. to boot from
root pool/data set, pass
root=zfs:root+pool/data+set).
The dataset can be at any depth, including being the pool's root
dataset (i.e. root=zfs:pool).
rootfstype=zfs is equivalent to
root=zfs:AUTO,
rootfstype=zfs root=pool/dataset is equivalent to
root=zfs:pool/dataset.
spl_hostid: passed to zgenhostid -f,
useful to override the /etc/hostid file baked into the
initrd.
bootfs.snapshot,
bootfs.snapshot=snapshot-name: enables
zfs-snapshot-bootfs.service, which creates a snapshot
$root_dataset@$(uname -r) (or, in the second form,
$root_dataset@snapshot-name) after pool import but before
the rootfs is mounted. Failure to create the snapshot is noted, but
booting continues.
bootfs.rollback,
bootfs.rollback=snapshot-name: enables
zfs-rollback-bootfs.service, which -Rf rolls
back to $root_dataset@$(uname -r) (or, in the second form,
$root_dataset@snapshot-name) after pool import but before
the rootfs is mounted. Failure to roll back will fall down to the rescue
shell. This has obvious potential for data loss: make sure your
persistent data is not below the rootfs and you don't care about any
intermediate snapshots.
If both bootfs.snapshot and
bootfs.rollback are set, bootfs.rollback is
ordered afterbootfs.snapshot.
zfs_force, zfs.force,
zfsforce: add -f to all
zpool import invocations. May be useful. Use with
caution.
