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<refentry id="systemd.special">

<refentryinfo>

<title>systemd.special</title>

<productname>systemd</productname>

<authorgroup>

<author>

<contrib>Developer</contrib>

<firstname>Lennart</firstname>

<surname>Poettering</surname>

<email>lennart@poettering.net</email>

</author>

</authorgroup>

</refentryinfo>

<refmeta>

<refentrytitle>systemd.special</refentrytitle>

<manvolnum>7</manvolnum>

</refmeta>

<refnamediv>

<refname>systemd.special</refname>

<refpurpose>Special systemd units</refpurpose>

</refnamediv>

<refsynopsisdiv>

<para><filename>basic.target</filename>,

<filename>bluetooth.target</filename>,

<filename>ctrl-alt-del.target</filename>,

<filename>cryptsetup.target</filename>,

<filename>dbus.service</filename>,

<filename>dbus.socket</filename>,

<filename>default.target</filename>,

<filename>display-manager.service</filename>,

<filename>emergency.target</filename>,

<filename>exit.target</filename>,

<filename>final.target</filename>,

<filename>getty.target</filename>,

<filename>graphical.target</filename>,

<filename>halt.target</filename>,

<filename>hibernate.target</filename>,

<filename>hybrid-sleep.target</filename>,

<filename>initrd-fs.target</filename>,

<filename>kbrequest.target</filename>,

<filename>kexec.target</filename>,

<filename>local-fs.target</filename>,

<filename>local-fs-pre.target</filename>,

<filename>multi-user.target</filename>,

<filename>network.target</filename>,

<filename>network-online.target</filename>,

<filename>nss-lookup.target</filename>,

<filename>nss-user-lookup.target</filename>,

<filename>paths.target</filename>,

<filename>poweroff.target</filename>,

<filename>printer.target</filename>,

<filename>reboot.target</filename>,

<filename>remote-fs.target</filename>,

<filename>remote-fs-pre.target</filename>,

<filename>rescue.target</filename>,

<filename>initrd-root-fs.target</filename>,

<filename>rpcbind.target</filename>,

<filename>runlevel2.target</filename>,

<filename>runlevel3.target</filename>,

<filename>runlevel4.target</filename>,

<filename>runlevel5.target</filename>,

<filename>shutdown.target</filename>,

<filename>sigpwr.target</filename>,

<filename>sleep.target</filename>,

<filename>smartcard.target</filename>,

<filename>sockets.target</filename>,

<filename>sound.target</filename>,

<filename>suspend.target</filename>,

<filename>swap.target</filename>,

<filename>sysinit.target</filename>,

<filename>syslog.socket</filename>,

<filename>system-update.target</filename>,

<filename>time-sync.target</filename>,

<filename>timers.target</filename>,

<filename>umount.target</filename>,

<filename>-.slice</filename>,

<filename>system.slice</filename>,

<filename>user.slice</filename>,

<filename>machine.slice</filename></para>

</refsynopsisdiv>

<refsect1>

<title>Description</title>

<para>A few units are treated specially by

systemd. They have special internal semantics and

cannot be renamed.</para>

</refsect1>

<refsect1>

<title>Special System Units</title>

<variablelist>

<varlistentry>

<term><filename>basic.target</filename></term>

<listitem>

<para>A special target unit

covering basic boot-up.</para>

<para>systemd automatically

adds dependencies of the types

<varname>Requires=</varname>

and <varname>After=</varname>

for this target unit to all

services (except for those

with

<varname>DefaultDependencies=no</varname>).</para>

<para>Usually this should

pull-in all mount points, swap

devices, sockets, timers, and

path units and other basic

initialization necessary for

general purpose

daemons.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>ctrl-alt-del.target</filename></term>

<listitem>

<para>systemd starts this

target whenever

Control+Alt+Del is pressed on

the console. Usually this

should be aliased (symlinked)

to

<filename>reboot.target</filename>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>cryptsetup.target</filename></term>

<listitem>

<para>A target that pulls in

setup services for all

encrypted block

devices.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>dbus.service</filename></term>

<listitem>

<para>A special unit for the

D-Bus bus daemon. As soon as

this service is fully started

up systemd will connect to it

and register its

service.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>dbus.socket</filename></term>

<listitem>

<para>A special unit for the

D-Bus system bus socket. All

units with

<varname>Type=dbus</varname>

automatically gain a

dependency on this

unit.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>default.target</filename></term>

<listitem>

<para>The default unit systemd

starts at bootup. Usually this

should be aliased (symlinked)

to

<filename>multi-user.target</filename>

or

<filename>graphical.target</filename>.</para>

<para>The default unit systemd

starts at bootup can be

overridden with the

<varname>systemd.unit=</varname>

kernel command line option.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>display-manager.service</filename></term>

<listitem>

<para>The display manager

service. Usually this should

be aliased (symlinked) to

<filename>gdm.service</filename>

or a similar display manager

service.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>emergency.target</filename></term>

<listitem>

<para>A special target unit

that starts an emergency

shell on the main

console. This unit is supposed

to be used with the kernel

command line option

<varname>systemd.unit=</varname>

and has otherwise little use.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>final.target</filename></term>

<listitem>

<para>A special target unit

that is used during the

shutdown logic and may be used

to pull in late services after

all normal services are

already terminated and all

mounts unmounted.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>getty.target</filename></term>

<listitem>

<para>A special target unit

that pulls in statically

configured local TTY

<filename>getty</filename>

instances.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>graphical.target</filename></term>

<listitem>

<para>A special target unit

for setting up a graphical

login screen. This pulls in

<filename>multi-user.target</filename>.</para>

<para>Units that are needed

for graphical logins shall add

<varname>Wants=</varname>

dependencies for their unit to

this unit (or

<filename>multi-user.target</filename>)

during installation. This is

best configured via

<varname>WantedBy=graphical.target</varname>

in the unit's

<literal>[Install]</literal>

section.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>hibernate.target</filename></term>

<listitem>

<para>A special target unit

for hibernating the

system. This pulls in

<filename>sleep.target</filename>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>hybrid-sleep.target</filename></term>

<listitem>

<para>A special target unit

for hibernating and suspending the

system at the same time. This pulls in

<filename>sleep.target</filename>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>halt.target</filename></term>

<listitem>

<para>A special target unit

for shutting down and halting

the system. Note that this

target is distinct from

<filename>poweroff.target</filename>

in that it generally really

just halts the system rather

than powering it down.</para>

<para>Applications wanting to

halt the system should start

this unit.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>initrd-fs.target</filename></term>

<listitem>

<para><citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>3</manvolnum></citerefentry>

automatically adds

dependencies of type

<varname>Before=</varname> to

<filename>sysroot-usr.mount</filename>

and all mount points found in

<filename>/etc/fstab</filename>

that have the

<option>auto</option> and

<option>x-initrd.mount</option>

mount options set.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>kbrequest.target</filename></term>

<listitem>

<para>systemd starts this

target whenever Alt+ArrowUp is

pressed on the console. This

is a good candidate to be

aliased (symlinked) to

<filename>rescue.target</filename>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>kexec.target</filename></term>

<listitem>

<para>A special target unit

for shutting down and rebooting the system via kexec.</para>

<para>Applications wanting to

reboot the system with kexec should start

this unit.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>local-fs.target</filename></term>

<listitem>

<para><citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>3</manvolnum></citerefentry>

automatically adds

dependencies of type

<varname>Before=</varname> to

all mount units that refer to

local mount points for this

target unit. In addition, it

adds dependencies of type

<varname>Wants=</varname> to

this target unit for those

mounts listed in

<filename>/etc/fstab</filename>

that have the

<option>auto</option> mount

option set.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>multi-user.target</filename></term>

<listitem>

<para>A special target unit

for setting up a multi-user

system (non-graphical). This

is pulled in by

<filename>graphical.target</filename>.</para>

<para>Units that are needed

for a multi-user system shall

add <varname>Wants=</varname>

dependencies for their unit to

this unit during

installation. This is best

configured via

<varname>WantedBy=multi-user.target</varname>

in the unit's

<literal>[Install]</literal>

section.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>network-online.target</filename></term>

<listitem>

<para>Units that strictly

require a configured network

connection should pull in

<filename>network-online.target</filename>

(via a

<varname>Wants=</varname> type

dependency) and order

themselves after it. This

target unit is intended to

pull in a service that delays

further execution until the

network is sufficiently set

up. What precisely this

requires is left to the

implementation of the network

managing service.</para>

<para>Note the distinction

between this unit and

<filename>network.target</filename>. This

unit is an active unit

(i.e. pulled in by the

consumer rather than the

provider of this

functionality) and pulls in a

service which possibly adds

substantial delays to further

execution. In contrast,

<filename>network.target</filename>

is a passive unit (i.e. pulled

in by the provider of the

functionality, rather than the

consumer) that usually does

not delay execution

much. Usually,

<filename>network.target</filename>

is part of the boot of most

systems, while

<filename>network-online.target</filename>

is not, except when at least

one unit requires it. Also see

<ulink

url="http://www.freedesktop.org/wiki/Software/systemd/NetworkTarget">Running

Services After the Network is

up</ulink> for more

information.</para>

<para>All mount units for

remote network file systems

automatically pull in this

unit, and order themselves

after it. Note that networking

daemons that simply provide

functionality to other hosts

generally do not need to pull

this in.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>paths.target</filename></term>

<listitem>

<para>A special target unit

that sets up all path units

(see

<citerefentry><refentrytitle>systemd.path</refentrytitle><manvolnum>5</manvolnum></citerefentry>

for details) that shall be

active after boot.</para>

<para>It is recommended that

path units installed by

applications get pulled in via

<varname>Wants=</varname>

dependencies from this

unit. This is best configured

via a

<varname>WantedBy=paths.target</varname>

in the path unit's

<literal>[Install]</literal>

section.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>poweroff.target</filename></term>

<listitem>

<para>A special target unit

for shutting down and powering off the system.</para>

<para>Applications wanting to

power off the system should start

this unit.</para>

<para><filename>runlevel0.target</filename>

is an alias for this target

unit, for compatibility with SysV.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>reboot.target</filename></term>

<listitem>

<para>A special target unit

for shutting down and rebooting the system.</para>

<para>Applications wanting to

reboot the system should start

this unit.</para>

<para><filename>runlevel6.target</filename>

is an alias for this target

unit, for compatibility with SysV.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>remote-fs.target</filename></term>

<listitem>

<para>Similar to

<filename>local-fs.target</filename>,

but for remote mount

points.</para>

<para>systemd automatically

adds dependencies of type

<varname>After=</varname> for

this target unit to all SysV

init script service units with

an LSB header referring to the

<literal>$remote_fs</literal>

facility.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>rescue.target</filename></term>

<listitem>

<para>A special target unit

for setting up the base system

and a rescue shell.</para>

<para><filename>runlevel1.target</filename>

is an alias for this target

unit, for compatibility with SysV.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>initrd-root-fs.target</filename></term>

<listitem>

<para><citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>3</manvolnum></citerefentry>

automatically adds

dependencies of type

<varname>Before=</varname> to

the

<filename>sysroot.mount</filename>

unit, which is generated from

the kernel command line.

</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>runlevel2.target</filename></term>

<term><filename>runlevel3.target</filename></term>

<term><filename>runlevel4.target</filename></term>

<term><filename>runlevel5.target</filename></term>

<listitem>

<para>These are targets that

are called whenever the SysV

compatibility code asks for

runlevel 2, 3, 4, 5,

respectively. It is a good

idea to make this an alias for

(i.e. symlink to)

<filename>multi-user.target</filename>

(for runlevel 2) or

<filename>graphical.target</filename>

(the others).</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>shutdown.target</filename></term>

<listitem>

<para>A special target unit

that terminates the services

on system shutdown.</para>

<para>Services that shall be

terminated on system shutdown

shall add <varname>Conflicts=</varname>

dependencies to this unit for

their service unit, which is

implicitly done when

<varname>DefaultDependencies=yes</varname>

is set (the default).</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>sigpwr.target</filename></term>

<listitem>

<para>A special target that is

started when systemd receives

the SIGPWR process signal,

which is normally sent by the

kernel or UPS daemons when

power fails.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>sleep.target</filename></term>

<listitem>

<para>A special target unit

that is pulled in by

<filename>suspend.target</filename>,

<filename>hibernate.target</filename>

and

<filename>hybrid-sleep.target</filename>

and may be used to hook units

into the sleep state

logic.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>sockets.target</filename></term>

<listitem>

<para>A special target unit

that sets up all socket

units.(see

<citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>

for details) that shall be

active after boot.</para>

<para>Services that can be

socket-activated shall add

<varname>Wants=</varname>

dependencies to this unit for

their socket unit during

installation. This is best

configured via a

<varname>WantedBy=sockets.target</varname>

in the socket unit's

<literal>[Install]</literal>

section.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>suspend.target</filename></term>

<listitem>

<para>A special target unit

for suspending the

system. This pulls in

<filename>sleep.target</filename>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>swap.target</filename></term>

<listitem>

<para>Similar to

<filename>local-fs.target</filename>, but for swap

partitions and swap

files.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>sysinit.target</filename></term>

<listitem>

<para>A special target unit

covering early boot-up scripts.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>syslog.socket</filename></term>

<listitem>

<para>The socket unit

syslog implementations should

listen on. All userspace log

messages will be made

available on this socket. For

more information about syslog

integration, please consult

the <ulink

url="http://www.freedesktop.org/wiki/Software/systemd/syslog">Syslog

Interface</ulink>

document.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>system-update.target</filename></term>

<listitem>

<para>A special target unit

that is used for off-line

system updates.

<citerefentry><refentrytitle>systemd-system-update-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>

will redirect the boot process

to this target if

<filename>/system-update</filename>

exists. For more information

see the <ulink

url="http://freedesktop.org/wiki/Software/systemd/SystemUpdates">System

Updates

Specification</ulink>.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>timers.target</filename></term>

<listitem>

<para>A special target unit

that sets up all timer

units (see

<citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>

for details) that shall be

active after boot.</para>

<para>It is recommended that

timer units installed by

applications get pulled in via

<varname>Wants=</varname>

dependencies from this

unit. This is best configured

via

<varname>WantedBy=timers.target</varname>

in the timer unit's

<literal>[Install]</literal>

section.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>umount.target</filename></term>

<listitem>

<para>A special target unit

that umounts all mount and

automount points on system

shutdown.</para>

<para>Mounts that shall be

unmounted on system shutdown

shall add Conflicts

dependencies to this unit for

their mount unit, which is

implicitly done when

<varname>DefaultDependencies=yes</varname>

is set (the default).</para>

</listitem>

</varlistentry>

</variablelist>

</refsect1>

<refsect1>

<title>Special System Units for Devices</title>

<para>Some target units are automatically pulled in as

devices of certain kinds show up in the system. These

may be used to automatically activate various services

based on the specific type of the available

hardware.</para>

<variablelist>

<varlistentry>

<term><filename>bluetooth.target</filename></term>

<listitem>

<para>This target is started

automatically as soon as a

Bluetooth controller is

plugged in or becomes

available at boot.</para>

<para>This may be used to pull

in Bluetooth management

daemons dynamically when

Bluetooth hardware is

found.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>printer.target</filename></term>

<listitem>

<para>This target is started

automatically as soon as a

printer is plugged in or

becomes available at

boot.</para>

<para>This may be used to pull

in printer management

daemons dynamically when

printer hardware is

found.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>smartcard.target</filename></term>

<listitem>

<para>This target is started

automatically as soon as a

smartcard controller is

plugged in or becomes

available at boot.</para>

<para>This may be used to pull

in smartcard management

daemons dynamically when

smartcard hardware is

found.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>sound.target</filename></term>

<listitem>

<para>This target is started

automatically as soon as a

sound card is plugged in or

becomes available at

boot.</para>

<para>This may be used to pull

in audio management daemons

dynamically when audio

hardware is found.</para>

</listitem>

</varlistentry>

</variablelist>

</refsect1>

<refsect1>

<title>Special Passive System Units </title>

<para>A number of special system targets are defined

that can be used to properly order boot-up of optional

services. These targets are generally not part of the

initial boot transaction, unless they are explicitly

pulled in by one of the implementing services. Note

specifically that these <emphasis>passive</emphasis>

target units are generally not pulled in by the

consumer of a service, but by the provider of the

service. This means: a consuming service should order

itself after these targets (as appropriate), but not

pull it in. A providing service should order itself

before these targets (as appropriate) and pull it in

(via a <varname>Wants=</varname> type

dependency).</para>

<para>Note that these passive units cannot be started

manually, i.e. <literal>systemctl start

time-sync.target</literal> will fail with an

error. They can only be pulled in by dependency. This

is enforced since they exist for ordering purposes

only and thus are not useful as only unit within a

transaction.</para>

<variablelist>

<varlistentry>

<term><filename>local-fs-pre.target</filename></term>

<listitem>

<para>This target unit is

automatically ordered before

all local mount points marked

with <option>auto</option>

(see above). It can be used to

execute certain units before

all local mounts.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>network.target</filename></term>

<listitem>

<para>This unit is supposed to

indicate when network

functionality is available,

but it is only very weakly

defined what that is supposed

to mean, with one exception:

at shutdown, a unit that is

ordered after

<filename>network.target</filename>

will be stopped before the

network -- to whatever level

it might be set up then -- is

shut down. Also see <ulink

url="http://www.freedesktop.org/wiki/Software/systemd/NetworkTarget">Running

Services After the Network is

up</ulink> for more

information. Also see

<filename>network-online.target</filename>

described above.</para>

<para>systemd automatically

adds dependencies of type

<varname>After=</varname> for

this target unit to all SysV

init script service units with

an LSB header referring to the

<literal>$network</literal>

facility.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>nss-lookup.target</filename></term>

<listitem>

<para>A target that should be

used as synchronization point

for all host/network name

service lookups. Note that

this is independent of

user/group name lookups for

which

<filename>nss-user-lookup.target</filename>

should be used. systemd

automatically adds

dependencies of type

<varname>After=</varname> for

this target unit to all SysV

init script service units with

an LSB header referring to the

<literal>$named</literal>

facility.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>nss-user-lookup.target</filename></term>

<listitem>

<para>A target that should be

used as synchronization point

for all user/group name

service lookups. Note that

this is independent of

host/network name lookups for

which

<filename>nss-lookup.target</filename>

should be used. </para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>remote-fs-pre.target</filename></term>

<listitem>

<para>This target unit is

automatically ordered before

all remote mount point units

(see above). It can be used to

run certain units before the

remote mounts are

established. Note that this

unit is generally not part of

the initial transaction,

unless the unit that wants to

be ordered before all remote

mounts pulls it in via a

<varname>Wants=</varname> type

dependency. If the unit wants

to be pulled in by the first

remote mount showing up, it

should use

<filename>network-online.target</filename>

(see above).</para>

<para>Again, this target unit

is <emphasis>not</emphasis>

suitable for pulling in other

units, it is only useful for

ordering.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>rpcbind.target</filename></term>

<listitem>

<para>systemd automatically

adds dependencies of type

<varname>After=</varname> for

this target unit to all SysV

init script service units with

an LSB header referring to the

<literal>$portmap</literal>

facility.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>time-sync.target</filename></term>

<listitem>

<para>systemd automatically

adds dependencies of type

<varname>After=</varname> for

this target unit to all SysV

init script service units with

an LSB header referring to the

<literal>$time</literal>

facility.</para>

</listitem>

</varlistentry>

</variablelist>

</refsect1>

<refsect1>

<title>Special User Units</title>

<para>When systemd runs as a user instance, the

following special units are available, which have

similar definitions as their system counterparts:

<filename>default.target</filename>,

<filename>shutdown.target</filename>,

<filename>sockets.target</filename>,

<filename>timers.target</filename>,

<filename>paths.target</filename>,

<filename>bluetooth.target</filename>,

<filename>printer.target</filename>,

<filename>smartcard.target</filename>,

<filename>sound.target</filename>.</para>

<para>In addition, the following special unit is

understood only when systemd runs as service instance:</para>

<variablelist>

<varlistentry>

<term><filename>exit.target</filename></term>

<listitem>

<para>A special service unit

for shutting down the

user service manager.</para>

<para>Applications wanting to

terminate the user service

manager should start this

unit. If systemd receives

<constant>SIGTERM</constant> or <constant>SIGINT</constant> when running

as user service daemon, it will

start this unit.</para>

<para>Normally, this pulls in

<filename>shutdown.target</filename>

which in turn should be

conflicted by all units that

want to be shut down on

user service manager exit.</para>

</listitem>

</varlistentry>

</variablelist>

</refsect1>

<refsect1>

<title>Special Slice Units</title>

<para>There are four <literal>.slice</literal> units

which form the basis of the hierarchy for assignment

of resources for services, users, and virtual machines

or containers.</para>

<variablelist>

<varlistentry>

<term><filename>-.slice</filename></term>

<listitem>

<para>The root slice is the

root of the hierarchy. It

usually does not contain units

directly, but may be used to

set defaults for the whole

tree.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>system.slice</filename></term>

<listitem>

<para>By default, all services

services started by

<command>systemd</command> are

found in this slice.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>user.slice</filename></term>

<listitem>

<para>By default, all user

processes and services started

on behalf of the user,

including the per-user systemd

instance are found in this

slice.</para>

</listitem>

</varlistentry>

<varlistentry>

<term><filename>machine.slice</filename></term>

<listitem>

<para>By defalt, all virtual

machines and containers

registered with

<command>systemd-machined</command>

are found in this slice.

</para>

</listitem>

</varlistentry>

</variablelist>

</refsect1>

<refsect1>

<title>See Also</title>

<para>

<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>bootup</refentrytitle><manvolnum>7</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>

</para>

</refsect1>

</refentry>