1.\" $NetBSD: swapon.8,v 1.8 1995/08/18 14:51:35 pk Exp $ 2.\" 3.\" Copyright (c) 1980, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)swapon.8 8.1 (Berkeley) 6/5/93 35.\" 36.Dd June 5, 1993 37.Dt SWAPON 8 38.Os BSD 4 39.Sh NAME 40.Nm swapon 41.Nd "specify additional device for paging and swapping" 42.Sh SYNOPSIS 43.Nm swapon 44.Fl a 45.Nm swapon 46.Ar special_file ... 47.Sh DESCRIPTION 48.Nm Swapon 49is used to specify additional devices on which paging and swapping 50are to take place. 51The system begins by swapping and paging on only a single device 52so that only one disk is required at bootstrap time. 53Calls to 54.Nm swapon 55normally occur in the system multi-user initialization file 56.Pa /etc/rc 57making all swap devices available, so that the paging and swapping 58activity is interleaved across several devices. 59.Pp 60Normally, the first form is used: 61.Bl -tag -width Ds 62.It Fl a 63All devices marked as ``sw'' 64swap devices in 65.Pa /etc/fstab 66are made available. 67.El 68.Pp 69The second form gives individual block devices as given 70in the system swap configuration table. The call makes only this space 71available to the system for swap allocation. 72.Sh SEE ALSO 73.Xr swapon 2 , 74.Xr fstab 5 , 75.Xr init 8 , 76.Xr rc 8 77.Sh FILES 78.Bl -tag -width /dev/[ru][pk]?b -compact 79.It Pa /dev/[ru][pk]?b 80standard paging devices 81.It Pa /etc/fstab 82ascii filesystem description table 83.El 84.Sh BUGS 85There is no way to stop paging and swapping on a device. 86It is therefore not possible to make use of devices which may be 87dismounted during system operation. 88.Sh HISTORY 89The 90.Nm 91command appeared in 92.Bx 4.0 . 93