1.\" Copyright (c) 1980, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)swapon.8 8.1 (Berkeley) 06/05/93 7.\" 8.Dd 9.Dt SWAPON 8 10.Os BSD 4 11.Sh NAME 12.Nm swapon 13.Nd "specify additional device for paging and swapping" 14.Sh SYNOPSIS 15.Nm swapon 16.Fl a 17.Nm swapon 18.Ar special_file ... 19.Sh DESCRIPTION 20.Nm Swapon 21is used to specify additional devices on which paging and swapping 22are to take place. 23The system begins by swapping and paging on only a single device 24so that only one disk is required at bootstrap time. 25Calls to 26.Nm swapon 27normally occur in the system multi-user initialization file 28.Pa /etc/rc 29making all swap devices available, so that the paging and swapping 30activity is interleaved across several devices. 31.Pp 32Normally, the first form is used: 33.Bl -tag -width Ds 34.It Fl a 35All devices marked as ``sw'' 36swap devices in 37.Pa /etc/fstab 38are made available. 39.El 40.Pp 41The second form gives individual block devices as given 42in the system swap configuration table. The call makes only this space 43available to the system for swap allocation. 44.Sh SEE ALSO 45.Xr swapon 2 , 46.Xr fstab 8 47.Xr init 8 48.Xr rc 8 49.Sh FILES 50.Bl -tag -width /dev/[ru][pk]?b -compact 51.It Pa /dev/[ru][pk]?b 52standard paging devices 53.It Pa /etc/fstab 54ascii filesystem description table 55.El 56.Sh BUGS 57There is no way to stop paging and swapping on a device. 58It is therefore not possible to make use of devices which may be 59dismounted during system operation. 60.Sh HISTORY 61The 62.Nm 63command appeared in 64.Bx 4.0 . 65