xref: /netbsd-src/share/man/man4/vnd.4 (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1.\"	$NetBSD: vnd.4,v 1.14 2006/02/01 03:22:14 cube Exp $
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37.Dd February 1, 2006
38.Dt VND 4
39.Os
40.Sh NAME
41.Nm vnd
42.Nd vnode disk driver
43.Sh SYNOPSIS
44.Cd "pseudo-device vnd"
45.Cd "options VND_COMPRESSION
46.Sh DESCRIPTION
47The
48.Nm
49driver provides a disk-like interface to a file.
50This is useful for a variety of applications, including swap files
51and building miniroot or floppy disk images.
52.Pp
53This document assumes that you're familiar with how to generate kernels,
54how to properly configure disks and pseudo-devices in a kernel
55configuration file.
56.Pp
57In order to compile in support for the vnd, you must add a line similar
58to the following to your kernel configuration file:
59.Bd -unfilled -offset indent
60pseudo-device	vnd		# vnode disk driver
61.Ed
62.Pp
63To also compile in support for reading compressed disk images,
64add the following option to your kernel config file:
65.Bd -unfilled -offset indent
66options        VND_COMPRESSION    # compressed vnd(4)
67.Ed
68.Pp
69Compressed disk images are expected in the cloop2 format,
70they can be created from "normal" disk images by the
71.Xr vndcompress 1
72program.
73.Pp
74There is a run-time utility that is used for configuring
75both compressed and uncompressed
76.Nm vnd Ns s .
77See
78.Xr vnconfig 8
79for more information.
80.Sh FILES
81.Bl -tag -width /dev/XXrXvndX -compact
82.It Pa /dev/{,r}vnd*
83vnd device special files.
84.El
85.Sh SEE ALSO
86.Xr config 1 ,
87.Xr vndcompress 1 ,
88.Xr MAKEDEV 8 ,
89.Xr fsck 8 ,
90.Xr mount 8 ,
91.Xr newfs 8 ,
92.Xr vnconfig 8
93.Sh HISTORY
94The vnode disk driver was originally written at the University of
95Utah.
96The compression handling is based on code by
97.An Cliff Wright
98.Aq cliff@snipe444.org .
99.Sh BUGS
100The
101.Nm
102driver does not work if the file does not reside in a local filesystem.
103