VNDCOMPRESS(1) BSD General Commands Manual VNDCOMPRESS(1)NAME
vndcompress, vnduncompress — compress/uncompress file system images
to/from cloop2 format
SYNOPSIS
vndcompress [-cd] disk/fs-image compressed-image [blocksize]
vnduncompress [-cd] compressed-image disk/fs-image
DESCRIPTION
The vndcompress program compresses an existing file system image into a
cloop2 compatible compressed file system image. An optional blocksize
can be given. If omitted, the default of 64kB is used.
The vnduncompress command decompress a cloop2-compressed file system
image back into a regular image.
The file system images that can be handled are not limited to any spe‐
cific file system, i.e. it is possible to handle images e.g. in ISO 9660
or UFS/FFS format. File system images in the cloop2 format are intended
to be used with the vnd(4) driver in compressed mode as configured by the
-z option of the vnconfig(8) program, and later mounted with the appro‐
priate -t option to mount(8).
OPTIONS
The following options are available:
-c Always compress, even if the program was started as
vnduncompress.
-d Always uncompress (decompress), even if the program was started
as vndcompress.
EXIT STATUS
The vndcompress and vnduncompress utilities exit with one of the follow‐
ing values:
0 The operation was performed successfully.
1 An error occurred.
EXAMPLES
To compress an existing CD-ROM file system image, run the following com‐
mands:
# vndcompress netbsd.iso netbsd.izo
Note that the resulting compressed image cannot be mounted directly via
NetBSD's vnd(4) and mount_cd9660(8) commands any longer. Instead, you
will have to use the -z option of vnconfig(8).
The following example decompresses an existing CD-ROM file system image
that was compressed in the cloop2 format into a regular file that can
then be mounted:
# vnconfig vnd0 KNOPPIX.iso
# mount -t cd9660 -o ro /dev/vnd0d /mnt
# vnduncompress /mnt/KNOPPIX/KNOPPIX /var/tmp/knoppix.iso
# umount /mnt
# vnconfig -u vnd0
#
# vnconfig vnd1 /var/tmp/knoppix.iso
# mount -t cd9660 -o ro /dev/vnd1d /mnt
# ls /mnt
.rr_moved cdrom floppy lib opt sbin usr
bin dev home mnt proc sys var
boot etc initrd none root tmp vmlinuz
# umount /mnt
# vnconfig -u vnd1
As an alternative, if your vnd(4) was compiled with VND_COMPRESSION, you
can use vnconfig(8) to access the cloop-compressed image directly, e.g.,
# vnconfig vnd0 KNOPPIX.iso
# mount -t cd9660 -o ro /dev/vnd0d /mnt
# vnconfig -z vnd1 /mnt/KNOPPIX/KNOPPIX
# mount -t cd9660 -o ro /dev/vnd1d /mnt2
# ls /mnt2
.rr_moved cdrom floppy lib opt sbin usr
bin dev home mnt proc sys var
boot etc initrd none root tmp vmlinuz
# df /mnt /mnt2
Filesystem Size Used Avail Capacity Mounted on
/dev/vnd0a 692M 692M 0B 100% /mnt
/dev/vnd1a 1.9G 1.9G 0B 100% /mnt2
# umount /mnt2
# vnconfig -u vnd1
# umount /mnt
# vnconfig -u vnd0
Note how the 1.9GB big filesystem on /mnt2 is mounted from the compressed
file stored on the 692MB CD mounted on /mnt. To create a compressed file
system image of an existing directory and mount it, run:
# makefs -t ffs include.fs /usr/include
# vndcompress include.fs include.fs.cloop2
# vnconfig -z vnd0 include.fs.cloop2
# mount -o ro /dev/vnd0a /mnt
# ls /mnt
To undo the steps, run:
# umount /mnt
# vnconfig -u vnd0
# rm /tmp/include.fs.cloop2
# rm /tmp/include.fs
SEE ALSOgzip(1), vnd(4), mount(8), mount_cd9660(8), vnconfig(8)AUTHORS
The vndcompress utility was written by Florian Stoehr
⟨netbsd@wolfnode.de⟩. The vndcompress manual page was written by Florian
Stoehr ⟨netbsd@wolfnode.de⟩ and Hubert Feyrer ⟨hubertf@NetBSD.org⟩.
BSD December 12, 2005 BSD
