Manual Reference Pages - GPTZFSBOOT (8)
- GPT bootcode for ZFS on BIOS-based computers
is used on BIOS-based computers to boot from a filesystem in
a ZFS pool.
is installed in a
partition of a GPT-partitioned disk with
The GPT standard allows a variable number of partitions, but
only boots from tables with 128 partitions or less.
tries to find all ZFS pools that are composed of BIOS-visible
hard disks or partitions on them.
looks for ZFS device labels on all visible disks and in discovered
supported partitions for all supported partition scheme types.
The search starts with the disk from which
itself was loaded.
Other disks are probed in BIOS defined order.
After a disk is probed and
determines that the whole disk is not a ZFS pool member, then
individual partitions are probed in their partition table order.
Currently GPT and MBR partition schemes are supported.
With the GPT scheme, only partitions of type
The first pool seen during probing is used as a default boot pool.
The filesystem specified by the
property of the pool is used as a default boot filesystem.
property is not set, then the root filesystem of the pool is used as
is loaded from the boot filesystem.
is present in the boot filesystem, boot options are read from it
in the same way as
The ZFS GUIDs of the first successfully probed device and the first
detected pool are made available to
will boot in fully automatic mode.
it is possible to interrupt the automatic boot process and interact with
through a prompt.
accepts all the options that
Filesystem specification and the path to
is different from
The format is
Both the filesystem and the path can be specified.
If only a path is specified, then the default filesystem is used.
If only a pool and filesystem are specified, then
is used as a path.
command can be used to query information about discovered pools.
The output format is similar to that of
The configured or automatically determined ZFS boot filesystem is
stored in the
variable, and also set as the initial value of the
boot code binary
parameters for the boot block
alternative parameters for the boot block
is typically installed in combination with a
gpart bootcode -b /boot/pmbr -p /boot/gptzfsboot -i 1 ada0
can also be installed without the PMBR:
gpart bootcode -p /boot/gptzfsboot -i 1 ada0
appeared in FreeBSD 7.3.
looks for ZFS meta-data only in MBR partitions
(known on FreeBSD as slices).
It does not look into BSD
partitions that are traditionally called partitions.
If a disklabel partition happens to be placed so that ZFS meta-data can be
found at the fixed offsets relative to a slice, then
will recognize the partition as a part of a ZFS pool,
but this is not guaranteed to happen.
This manual page was written by
.An Andriy Gapon Aq avg@FreeBSD.org .
Visit the GSP FreeBSD Man Page Interface.
Output converted with manServer 1.07.