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.Dd Apr 20, 2017
.Dt ZFSLOADER 5
.Os
.Sh NAME
.Nm zfsloader
.Nd kernel bootstrapping final stage
.Sh DESCRIPTION
.Nm
is an extended variant of
.Xr loader 5
with added support for booting from ZFS.
This document describes only differences from
.Xr loader 5 .
.Ss ZFS Features
.Nm
supports the following format for specifying ZFS filesystems which
can be used wherever
.Xr loader 5
refers to a device specification:
.Pp
.Ar zfs:pool/filesystem:
.Pp
where
.Pa pool/filesystem
is a ZFS filesystem name as described in
.Xr zfs 1M .
.Pp
If the variable
.Va fstype
is not set, but
.Va currdev
refers to a ZFS filesystem, then
.Nm
will instruct kernel to use that filesystem as the root filesystem.
.Ss ZFS Command Extensions
.Bl -tag -width Ds -compact
.It Ic lsdev Op Fl v
Lists ZFS pools in addition to disks and partitions.
Adding
.Fl v
shows more ZFS pool details in a format that resembles
.Nm zpool Cm status
output.
.Pp
.It Ic lszfs Ar filesystem
A ZFS extended command that can be used to explore the ZFS filesystem
hierarchy in a pool.
Lists the immediate children of the
.Ar filesystem .
The filesystem hierarchy is rooted at a filesystem with the same name
as the pool.
.El
.Sh FILES
.Bl -tag -width /boot/zfsloader -compact
.It Pa /boot/zfsloader
.Nm
itself.
.El
.Sh EXAMPLES
Set the default device used for loading a kernel from a ZFS filesystem:
.Bd -literal -offset indent
set currdev=zfs:rpool/ROOT/knowngood:
.Ed
.Sh SEE ALSO
.Xr zfs 1M ,
.Xr zpool 1M ,
.Xr gptzfsboot 5 ,
.Xr loader 5
.Sh NOTES
Although setting the
.Va currdev
as shown in the example above is supported, it is advisable to use loader
beadm command or boot environment menu instead. The reason is, the beadm
or menu selection will also instruct loader to clean up the currently set
configuration and load configuration from the new boot environment.