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systemd.swap


SYNOPSIS

       swap.swap


DESCRIPTION

       A unit configuration file whose name ends in ".swap" encodes
       information about a swap device or file for memory paging controlled
       and supervised by systemd.

       This man page lists the configuration options specific to this unit
       type. See systemd.unit(5) for the common options of all unit
       configuration files. The common configuration items are configured in
       the generic [Unit] and [Install] sections. The swap specific
       configuration options are configured in the [Swap] section.

       Additional options are listed in systemd.exec(5), which define the
       execution environment the swapon(8) binary is executed in, and in
       systemd.kill(5), which define the way the processes are terminated, and
       in systemd.resource-control(5), which configure resource control
       settings for the processes of the service.

       Swap units must be named after the devices or files they control.
       Example: the swap device /dev/sda5 must be configured in a unit file
       dev-sda5.swap. For details about the escaping logic used to convert a
       file system path to a unit name, see systemd.unit(5).

       All swap units automatically get the appropriate dependencies on the
       devices or on the mount points of the files they are activated from.

       Swap units with DefaultDependencies= enabled implicitly acquire a
       conflicting dependency to umount.target so that they are deactivated at
       shutdown.


FSTAB

       Swap units may either be configured via unit files, or via /etc/fstab
       (see fstab(5) for details). Swaps listed in /etc/fstab will be
       converted into native units dynamically at boot and when the
       configuration of the system manager is reloaded. See systemd-fstab-
       generator(8) for details about the conversion.

       If a swap device or file is configured in both /etc/fstab and a unit
       file, the configuration in the latter takes precedence.

       When reading /etc/fstab a few special options are understood by systemd
       which influence how dependencies are created for swap units.

       noauto, auto
           With noauto the swap unit will not be added as a dependency for
           swap.target. This means that it will not be activated automatically
           during boot, unless it is pulled in by some other unit. Option auto
           has the opposite meaning and is the default.

       nofail
           dependency on the respective device unit is automatically created.
           (See systemd.device(5) for more information.) If this refers to a
           file, a dependency on the respective mount unit is automatically
           created. (See systemd.mount(5) for more information.) This option
           is mandatory.

       Priority=
           Swap priority to use when activating the swap device or file. This
           takes an integer. This setting is optional.

       Options=
           May contain an option string for the swap device. This may be used
           for controlling discard options among other functionality, if the
           swap backing device supports the discard or trim operation. (See
           swapon(8) for more information.)

       TimeoutSec=
           Configures the time to wait for the swapon command to finish. If a
           command does not exit within the configured time, the swap will be
           considered failed and be shut down again. All commands still
           running will be terminated forcibly via SIGTERM, and after another
           delay of this time with SIGKILL. (See KillMode= in
           systemd.kill(5).) Takes a unit-less value in seconds, or a time
           span value such as "5min 20s". Pass "0" to disable the timeout
           logic. Defaults to DefaultTimeoutStartSec= from the manager
           configuration file (see systemd-system.conf(5)).

       Check systemd.exec(5) and systemd.kill(5) for more settings.


SEE ALSO

       systemd(1), systemctl(1), systemd.unit(5), systemd.exec(5),
       systemd.kill(5), systemd.resource-control(5), systemd.device(5),
       systemd.mount(5), swapon(8), systemd-fstab-generator(8),
       systemd.directives(7)


systemd 219 SYSTEMD.SWAP(5)



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