Copyright (c) 1993 University of Utah.
Copyright (c) 1980, 1989, 1991, 1993
The Regents of the University of California. All rights reserved.
Copyright (c) 2000
Poul-Henning Kamp All rights reserved.

This code is derived from software contributed to Berkeley by
the Systems Programming Group of the University of Utah Computer
Science Department.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. All advertising materials mentioning features or use of this software
must display the following acknowledgement:
This product includes software developed by the University of
California, Berkeley and its contributors.
4. Neither the name of the University nor the names of its contributors
may be used to endorse or promote products derived from this software
without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.

@(#)vnconfig.8 8.1 (Berkeley) 6/5/93
from: src/usr.sbin/vnconfig/vnconfig.8,v 1.19 2000/12/27 15:30:29

$FreeBSD: head/sbin/mdconfig/mdconfig.8 104018 2002-09-26 21:29:10Z phk $

.Dd December 31, 2000 .Dt MDCONFIG 8 .Os .Sh NAME .Nm mdconfig .Nd configure and enable memory disks .Sh SYNOPSIS .Nm .Fl a .Fl t Ar type .Oo .Fl o .Oo Cm no Oc Ns Ar option .Oc .Op Fl s Ar size .Op Fl f Ar file .Op Fl u Ar unit .Nm .Fl d .Fl u Ar unit .Nm .Fl l .Op Fl u Ar unit .Sh DESCRIPTION The .Nm utility configures and enables .Xr md 4 devices.

p Options indicate an action to be performed: l -tag -width indent t Fl a Attach a memory disk. This will configure and attach a memory disk with the parameters specified and attach it to the system. t Fl d Detach a memory disk from the system and release all resources. t Fl t Ar type Select the type of the memory disk. l -tag -width "preload" t Cm malloc Storage for this type of memory disk is allocated with .Xr malloc 9 . This limits the size to the malloc bucket limit in the kernel. t Cm vnode A file specified with .Fl f Ar file becomes the backingstore for this memory disk. t Cm swap swapspace is used to back this memory disk. .El t Fl f Ar file Filename to use for the vnode type memory disk. t Fl l List information about configured .Xr md 4 devices. If the .Fl u option is used in conjuction with this, the output is limited to information on the specified device. t Fl s Ar size Size of the memory disk. .Ar Size is the number of 512 bytes sectors unless suffixed with a .Cm k , m , or .Cm g which denotes kilobyte, megabyte and gigabyte respectively. t Fl o Oo Cm no Oc Ns Ar option Set or reset options. l -tag -width indent t Oo Cm no Oc Ns Cm reserve Allocate and reserve all needed storage from the start, rather than as needed. t Oo Cm no Oc Ns Cm cluster Enable clustering on this disk. t Oo Cm no Oc Ns Cm compress Enable/Disable compression features to reduce memory usage. t Oo Cm no Oc Ns Cm force Disable/Enable extra sanity checks to prevent the user from doing something that might adversely affect the system. t Oo Cm no Oc Ns Cm readonly Enable/Disable readonly mode. .El t Fl u Ar unit Request a specific unit number for the .Xr md 4 device instead of automatic allocation. .El .Sh EXAMPLES To create a 4 megabyte .Xr malloc 9 backed memory disk. The name of the allocated unit will be output on stdout like .Dq Li md3 :

p .Dl mdconfig -a -t malloc -s 4m

p To create a disk named

a /dev/md4 with

a /tmp/boot.flp as backing:

p .Dl mdconfig -a -t vnode -f /tmp/boot.flp -u 4

p To detach and free all resources used by

a /dev/md4 :

p .Dl mdconfig -d -u 4

p To create and mount a 128MByte swap backed file system on

a /tmp : d -literal -offset indent mdconfig -a -t swap -s 128M -u 10 newfs -U /dev/md10 mount /dev/md10 /tmp chmod 1777 /tmp .Ed .Sh SEE ALSO .Xr md 4 , .Xr disklabel 8 , .Xr fdisk 8 , .Xr malloc 9 .Sh HISTORY The .Nm utility first appeared in .Fx 5.0 as a cleaner replacement for the .Xr vn 4 and .Xr vnconfig 8 combo. .Sh AUTHORS The .Nm utility was written by .An Poul-Henning Kamp .Aq phk@FreeBSD.org .