vnconfig(8) - NetBSD Manual Pages

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VNCONFIG(8)             NetBSD System Manager's Manual             VNCONFIG(8)


NAME

     vnconfig -- configure vnode disks


SYNOPSIS

     vnconfig [-crvz] [-f disktab] [-t typename] vnode_disk regular_file
              [geomspec]
     vnconfig -u [-Fv] vnode_disk
     vnconfig -l [vnode_disk]


DESCRIPTION

     The vnconfig command configures vnode pseudo disk devices.  It will asso-
     ciate the vnode disk vnode_disk with the regular file regular_file allow-
     ing the latter to be accessed as though it were a disk.  Hence a regular
     file within the filesystem can be used for swapping or can contain a
     filesystem that is mounted in the name space.  The vnode_disk is a spe-
     cial file of raw partition or name of vnode disk like vnd0.

     Options indicate an action to be performed:

     -c      Configures the device.  If successful, references to vnode_disk
             will access the contents of regular_file.

             If geomspec is specified, the vnode device will emulate the spec-
             ified disk geometry.  The format of the geomspec argument is:

                   secsize/nsectors/ntracks/ncylinders

             If geometry is not specified, the kernel will choose a default
             based on 1MB cylinders.  secsize is the number of bytes per sec-
             tor.  It must be an even multiple of 512.  nsectors is the number
             of sectors per track.  ntracks is the number of tracks per cylin-
             der.  ncylinders is the number of cylinders in the device.

     -F      Force unconfiguration if the device is in use.  Does not imply
             -u.

     -f disktab
             Specifies that the -t option should look up in disktab instead of
             in /etc/disktab.

     -l      List the vnd devices and indicate which ones are in use.  If a
             specific vnode_disk is given, then only that will be described.

     -t typename
             If configuring the device, look up typename in /etc/disktab and
             use the geometry specified in the entry.  This option and the
             geomspec argument are mutually exclusive.

     -r      Configure the device as read-only.

     -u      Unconfigures the device.

     -v      Print messages to stdout describing actions taken.

     -z      Assume that regular_file is a compressed disk image in cloop2
             format, and configure it read-only.  See the vndcompress(1) man-
             page on how to create such an image.

     If no action option is given, -c is assumed.


FILES

     /dev/rvnd??
     /dev/vnd??
     /etc/disktab


EXAMPLES

           vnconfig vnd0 /tmp/diskimage
     or
           vnconfig /dev/rvnd0c /tmp/diskimage

     Configures the vnode disk vnd0.  Please note that use of the second form
     of the command is discouraged because it requires knowledge of the raw
     partition which varies between architectures.

           vnconfig vnd0 /tmp/floppy.img 512/18/2/80

     Configures the vnode disk vnd0 emulating the geometry of 512 bytes per
     sector, 18 sectors per track, 2 tracks per cylinder, and 80 cylinders
     total.

           vnconfig -t floppy vnd0 /tmp/floppy.img

     Configures the vnode disk vnd0 using the geometry specified in the floppy
     entry in /etc/disktab.

           vnconfig -u vnd0

     Unconfigures the vnd0 device.


SEE ALSO

     opendisk(3), vnd(4), mount(8), swapctl(8), umount(8)


HISTORY

     The vnconfig command appeared in NetBSD 1.0.


BUGS

     This command should really be named vndconfig.

NetBSD 6.1.2                     July 16, 2005                    NetBSD 6.1.2