SWAPON(8)                           Linux Programmer's Manual                           SWAPON(8)



NAME
       swapon, swapoff - enable/disable devices and files for paging and swapping

SYNOPSIS
       /sbin/swapon [-h -V]
       /sbin/swapon -a [-v] [-e]
       /sbin/swapon [-v] [-p priority]  specialfile ...
       /sbin/swapon [-s]
       /sbin/swapoff [-h -V]
       /sbin/swapoff -a
       /sbin/swapoff specialfile ...

DESCRIPTION
       Swapon  is  used to specify devices on which paging and swapping are to take place.  Calls
       to swapon normally occur in the system multi-user initialization file /etc/rc  making  all
       swap  devices  available,  so  that the paging and swapping activity is interleaved across
       several devices and files.

       Normally, the first form is used:

       -h     Provide help

       -V     Display version

       -s     Display swap usage summary by device. Equivalent to "cat /proc/swaps".  Not  avail-
              able before Linux 2.1.25.

       -a     All  devices  marked  as  ''swap''  swap  devices in /etc/fstab are made available.
              Devices that are already running as swap are silently skipped.

       -e     When -a is used with swapon, -e makes swapon silently  skip  devices  that  do  not
              exist.

       -p priority
              Specify  priority for swapon.  This option is only available if swapon was compiled
              under and is used under a 1.3.2 or later kernel.  priority is a value between 0 and
              32767.  See  swapon(2)  for a full description of swap priorities. Add pri=value to
              the option field of /etc/fstab for use with swapon -a.

       specialfile means file, device, LABEL=label_name or UUID=uuid.

       Swapoff disables swapping on the specified devices and files.  When the -a flag is  given,
       swapping  is  disabled  on  all  known  swap devices and files (as found in /proc/swaps or
       /etc/fstab).

NOTE
       You should not use swapon on a file with holes.  Swap over NFS may not work.

SEE ALSO
       swapon(2), swapoff(2), fstab(5), init(8), mkswap(8), rc(8), mount(8)

FILES
       /dev/hd??  standard paging devices
       /dev/sd??  standard (SCSI) paging devices
       /etc/fstab ascii filesystem description table

HISTORY
       The swapon command appeared in 4.0BSD.



Linux 1.x                               25 September 1995                               SWAPON(8)