overlay-diskfile(8)
===================
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NAME
----
overlay-diskfile - Support for using diskfile filesystem.

SYNOPSIS
--------
*overlay-diskfile* _mount/path_ [ _diskfile_ [ _index_ ] ]

DESCRIPTION
-----------

*overlay-diskfile* is a support script for pre-mounting a diskfile to
provide the LOWER or UPPER filesystem for a subhost. It is typically
used in the subhost configuration to be invoked as part of determining
the filesystem path.

OPTIONS
-------

no options.

EXAMPLES
--------

.Use a whole diskfile filesystem as LOWER
====
----
LOWER=!overlay-diskfile mnt/ disk.img
----
====

The above mounts the disk.img filesystem onto +mnt+ and provides that
as the LOWER filesystem.

.Use a diskfile partition 2 as LOWER
====
----
LOWER=!overlay-diskfile mnt/ disk.img 2
----
====

The above mounts the second partition onto +mnt+ and provides that as
the LOWER filesystem.

.Use a subtree of a diskfile partition 2 as LOWER
====
----
LOWER=!overlay-diskfile mnt/some/path disk.img 2
----
====

The above mounts the second partition onto +mnt+ and provides the path
+mnt/some/path+ that as the LOWER filesystem.

.Use second partition diskfile filesystem subtrees for UPPER and WORK.
====
----
UPPER=!overlay-diskfile mnt/some/upper/path disk.img 2
WORK= mnt/some/work/path
----
====

The above mounts the second partition of disk.img and uses
+mnt/some/upper/path+ as UPPER and +mnt/some/work/path+ as WORK. Note
that UPPER and WORK must always be subtrees from the same filesystem.


SEE ALSO
--------

*overlay-boot*, *overlay-stop*
