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MKIMG(1)		  BSD General Commands Manual		      MKIMG(1)

     mkimg -- utility to make disk images

     mkimg [-H heads] [-P blksz] [-S secsz] [-T	tracksz] [-b bootcode]
	   [-f format] [-o outfile] [-v] [-y] -s scheme	-p partition
	   [-p partition ...]
     mkimg --formats | --schemes | --version

     The mkimg utility creates a disk image from the raw partition contents
     specified with the	partition argument(s) and using	the partitioning
     scheme specified with the scheme argument.	 The disk image	is written to
     stdout by default or the file specified with the outfile argument.	 The
     image file	is a raw disk image by default,	but the	format of the image
     file can be specified with	the format argument.

     The disk image can	be made	bootable by specifying the scheme-specific
     boot block	contents with the bootcode argument and, depending on the
     scheme, with a boot partition.  The contents of such a boot partition is
     provided like any other partition and the mkimg utility does not treat it
     any differently from other	partitions.

     Some partitioning schemes need a disk geometry and	for those the mkimg
     utility accepts the tracksz and heads arguments, specifying the number of
     sectors per track and the number of heads per cylinder (resp.)

     Both the logical and physical sector size can be specified	and for	that
     the mkimg utility accepts the secsz and blksz arguments.  The secsz argu-
     ment is used to specify the logical sector	size.  This is the sector size
     reported by a disk	when queried for its capacity.	Modern disks use a
     larger sector size	internally, referred to	as block size by the mkimg
     utility and this can be specified by the blksz argument.  The mkimg util-
     ity will use the (physical) block size to determine the start of parti-
     tions and to round	the size of the	disk image.

     The [-v] option increases the level of output that	the mkimg utility

     The [-y] option is	used for testing purposes only and is not to be	used
     in	production.  When present, the mkimg utility will generate predictable
     values for	Universally Unique Identifiers (UUIDs) and time	stamps so that
     consecutive runs of the mkimg utility will	create images that are identi-

     A set of long options exist to query about	the mkimg utilty itself.  Op-
     tions in this set should be given by themselves because the mkimg utility
     exits immediately after providing the requested information.  The version
     of	the mkimg utility is printed when the --version	option is given.  The
     list of supported output formats is printed when the --formats option is
     given and the list	of supported partitioning schemes is printed when the
     --schemes option is given.	 Both the format and scheme lists a space-sep-
     arated lists for easy handling in scripts.

     For a more	descriptive list of supported partitioning schemes or sup-
     ported output format, or for a detailed description of how	to specify
     partitions, run the mkimg utility without any arguments.  This will print
     a usage message with all the necessary details.

     TMPDIR  Directory to put temporary	files in; default is /tmp.

     To	create a bootable disk image that is partitioned using the GPT scheme
     and containing a root file	system that was	previously created using
     makefs and	also containing	a swap partition, run the mkimg	utility	as
	   % mkimg -s gpt -b /boot/pmbr	-p freebsd-boot:=/boot/gptboot -p
	   freebsd-ufs:=root-file-system.ufs -p	freebsd-swap::1G -o gpt.img

     The command line given above results in a raw image file.	This is	be-
     cause no output format was	given.	To create a VMDK image for example,
     add the -f	vmdk argument to the mkimg utility and name the	output file

     A nested partitioning scheme is created by	running	the mkimg utility
     twice.  The output	of the first will be fed as the	contents of a parti-
     tion to the second.  This can be done using a temporary file, like	so:
	   % mkimg -s bsd -b /boot/boot	-p freebsd-ufs:=root-file-system.ufs
	   -p freebsd-swap::1G -o /tmp/bsd.img
	   % mkimg -s mbr -b /boot/mbr -p freebsd:=/tmp/bsd.img	-o mbr-bsd.img

     Alternatively, the	mkimg utility can be run in a cascaded fashion,
     whereby the output	of the first is	fed directly into the second.  To do
     this, run the mkimg utility as follows:
	   % mkimg -s mbr -b /boot/mbr -p freebsd:-'mkimg -s bsd -b /boot/boot
	   -p freebsd-ufs:=root-file-system.ufs	-p freebsd-swap::1G' -o

     To	accomodate the need to have partitions named or	numbered in a certain
     way, the mkimg utility allows for the specification of empty partitions.
     For example, to create an image that is compatible	with partition layouts
     found in /etc/disktab, the	'd' partition often needs to be	skipped.  This
     is	accomplished by	inserting an unused partition after the	first 2	parti-
     tion specifications.  It is worth noting at this time that	the BSD	scheme
     will automatically	skip the 'c' partition by virtue of it referring to
     the entire	disk.  To create an image that is compatible with the qp120at
     disk, use the mkimg utility as follows:
	   % mkimg -s bsd -b /boot/boot	-p freebsd-ufs:=root-file-system.ufs
	   -p freebsd-swap::20M	-p- -p-	-p- -p-	-p
	   freebsd-ufs:=usr-file-system.ufs -o bsd.img

     For partitioning schemes that feature partition labels, the mkimg utility
     supports assigning	labels to the partitions specified.  In	the following
     example the file system partition is labeled as 'backup':
	   % mkimg -s gpt -p freebsd-ufs/backup:=file-system.ufs -o gpt.img

     gpart(8) makefs(8)	mdconfig(8) newfs(8)

     The mkimg utility first appeared in FreeBSD 10.1.

     The mkimg utility and manpage were	written	by Marcel Moolenaar

BSD			      September	27, 2014			   BSD


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