Cloop

2007-10-27T11:48:06Z

Volkan YAZICI: Mention about zlib_inflate/deflate just before issuing insmod cloop.ko

= Introduction =

'''Cloop''', is a [[http://www.wikipedia.org/wiki/Kernel Kernel] (computers)] [[http://www.wikipedia.org/wiki/module module]] to add support for [[http://www.wikipedia.org/wiki/filesystem filesystem]-independent,]
transparently decompressed, read-only, block devices.

= Where to download =

* <s>[http://developer.linuxtag.net/knoppix/sources/ http://developer.linuxtag.net/knoppix/sources/]</s> (This link doesn't work) <br>
* [http://debian-knoppix.alioth.debian.org/sources/ http://debian-knoppix.alioth.debian.org/sources/] (Alternative link)

Use version 1.xx if you have a 2.4 kernel, or version 2.xx for 2.6 kernel. Versions 0.xx are too old, probably won't work well.

= Installation =
make KERNEL_DIR=/path/to/linux-kernel/sources

Issue these commands as [[root]]
mkdir -p /lib/modules/misc && cp cloop.ko /lib/modules/misc/
depmod -a
mknod /dev/cloop b 240 0

= Usage =

== Creating a compressed image: ==

create_compressed_fs image blocksize > image.cloop_compressed

Where
blocksize must be a multiple of 512 bytes. Make sure you have enough
swap to hold the entire compressed image in virtual memory!

The command may also be used in [[Linux]] [[command line]] pipe sequences. Use "-" as the image filename. The dash, "-" will cause the command to read data from stdin, as in

mkisofs -r datadir | create_compressed_fs - 65536 > datadir.iso.compressed

== Mounting a compressed image (see above for device creation): ==

# Unless zlib_deflate/inflate features are built-in to your kernel, you may
# also need to install related kernel modules.
modprobe zlib_inflate
modprobe zlib_deflate

insmod cloop.ko file=/path/to/compressed/image

[[mount]] -o ro -t whatever /dev/cloop /mnt/compressed

== If you boot from the LiveDVD and want to mount a compressed image, which you have saved on the disc: ==
Check with the 'mount' command which /dev/cloopX (where X goes from 0 to 7, because cloop can do just 8 devices)
are already in use.
Then mount your compressed image to a cloop device via

iosetup /dev/cloopX /path/to/compressed/image

[[mount]] -o ro /dev/cloopX /mnt/compressed

[[Category:Useful Linux Commands]]

Knoppix Documentation Wiki - User contributions [en]

Cloop