1.\" Copyright (c) 1993 University of Utah. 2.\" Copyright (c) 1980, 1989, 1991, 1993 3.\" The Regents of the University of California. All rights reserved. 4.\" Copyright (c) 2000 5.\" Poul-Henning Kamp All rights reserved. 6.\" 7.\" This code is derived from software contributed to Berkeley by 8.\" the Systems Programming Group of the University of Utah Computer 9.\" Science Department. 10.\" 11.\" Redistribution and use in source and binary forms, with or without 12.\" modification, are permitted provided that the following conditions 13.\" are met: 14.\" 1. Redistributions of source code must retain the above copyright 15.\" notice, this list of conditions and the following disclaimer. 16.\" 2. Redistributions in binary form must reproduce the above copyright 17.\" notice, this list of conditions and the following disclaimer in the 18.\" documentation and/or other materials provided with the distribution. 19.\" 3. All advertising materials mentioning features or use of this software 20.\" must display the following acknowledgement: 21.\" This product includes software developed by the University of 22.\" California, Berkeley and its contributors. 23.\" 4. Neither the name of the University nor the names of its contributors 24.\" may be used to endorse or promote products derived from this software 25.\" without specific prior written permission. 26.\" 27.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37.\" SUCH DAMAGE. 38.\" 39.\" @(#)vnconfig.8 8.1 (Berkeley) 6/5/93 40.\" from: src/usr.sbin/vnconfig/vnconfig.8,v 1.19 2000/12/27 15:30:29 41.\" 42.\" $FreeBSD$ 43.\" 44.Dd December 31, 2000 45.Dt MDCONFIG 8 46.Os FreeBSD 47.Sh NAME 48.Nm mdconfig 49.Nd configure and enable memory disks 50.Sh SYNOPSIS 51.Nm 52.Fl a 53.Fl t Ar type 54.Oo 55.Fl o 56.Oo Cm no Oc Ns Ar option 57.Oc 58.Op Fl s Ar size 59.Op Fl f Ar file 60.Op Fl u Ar unit 61.Nm 62.Fl d 63.Fl u Ar unit 64.Nm 65.Fl l 66.Op Fl u Ar unit 67.Sh DESCRIPTION 68The 69.Nm 70command configures and enables 71.Xr md 4 72devices. 73.Pp 74Options indicate an action to be performed: 75.Bl -tag -width indent 76.It Fl a 77Attach a memory disk. 78This will configure and attach a memory disk with the 79parameters specified and attach it to the system. 80.It Fl d 81Detach a memory disk from the system and release all resources. 82.It Fl t Ar type 83Select the type of the memory disk. 84.Bl -tag -width "preload" 85.It Cm malloc 86Storage for this type of memory disk is allocated with 87.Xr malloc 9 . 88This limits the size to the malloc bucket limit in the kernel. 89.It Cm vnode 90A file specified with 91.Fl f Ar file 92becomes the backingstore for this memory disk. 93.It Cm swap 94swapspace is used to back this memory disk. 95.El 96.It Fl f Ar file 97Filename to use for the vnode type memory disk. 98.It Fl l 99List information about configured 100.Xr md 4 101devices. If the 102.Fl u 103option is used in conjuction with this, the output is limited to 104information on the specified device. 105.It Fl s Ar size 106Size of the memory disk. 107.Ar Size 108is the number of 512 bytes sectors unless suffixed with a 109.Cm k , m , 110or 111.Cm g 112which 113denotes kilobyte, megabyte and gigabyte respectively. 114.It Xo 115.Fl o Oo Cm no Oc Ns Ar option 116.Xc 117Set or reset options. 118.Bl -tag -width indent 119.It Xo 120.Oo Cm no Oc Ns Cm reserve 121.Xc 122Allocate and reserve all needed storage from the start, rather than as needed. 123.It Xo 124.Oo Cm no Oc Ns Cm cluster 125.Xc 126Enable clustering on this disk. 127.It Xo 128.Oo Cm no Oc Ns Cm compress 129.Xc 130Enable/Disable compression features to reduce memory usage. 131.It Xo 132.Oo Cm no Oc Ns Cm readonly 133.Xc 134Enable/Disable readonly mode. 135.El 136.It Fl u Ar unit 137Request a specific unit number for the 138.Xr md 4 139device instead of automatic allocation. 140.El 141.Sh EXAMPLES 142To create a 4 megabyte 143.Xr malloc 9 144backed memory disk. 145The name of the allocated unit will be output on stdout like 146.Dq Li md3 : 147.Pp 148.Dl mdconfig -a -t malloc -s 4m 149.Pp 150To create a disk named 151.Pa /dev/md4 152with 153.Pa /tmp/boot.flp 154as backing: 155.Pp 156.Dl mdconfig -a -t vnode -f /tmp/boot.flp -u 4 157.Pp 158To detach and free all resources used by 159.Pa /dev/md4 : 160.Pp 161.Dl mdconfig -d -u 4 162.Pp 163To create and mount a 128MByte swap backed filesystem on 164.Pa /tmp : 165.Bd -literal -offset indent 166mdconfig -a -t swap -s 128M -u 10 167disklabel -r -w md10 auto 168newfs /dev/md10c 169tunefs -n enable /dev/md10c 170mount /dev/md10c /tmp 171chmod 1777 /tmp 172.Ed 173.Sh SEE ALSO 174.Xr md 4 , 175.Xr disklabel 8 , 176.Xr fdisk 8 , 177.Xr malloc 9 178.Sh HISTORY 179The 180.Nm 181first appeared in 182.Fx 5.0 183as a cleaner replacement for the 184.Xr vn 4 185and 186.Xr vnconfig 8 187combo. 188.Sh AUTHORS 189The 190.Nm 191program was written by 192.An Poul-Henning Kamp 193.Aq phk@FreeBSD.org . 194