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I have come across a .service that contains the following:

[Install] WantedBy=multi-user.target

The original .service file can be found here.

What is the the meaning of multi-user.target?

I am on Ubuntu 16.04 LTS.

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  • 3
    Possible duplicate of What is systemd's target, service and socket? Commented Nov 15, 2017 at 8:49
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    It's not a proper duplicate, as (reading beyond the title) this question is asking about the [Install] section of a unit file. Ironically, it is the very next table down from the one hyperlinked in the question. Commented Nov 15, 2017 at 11:52
  • 1
    This new related question has a lot more details in the answer and is very well worth reading. Commented Mar 14, 2019 at 23:13
  • It really is, thanks for pointing there @Wildcard. Commented Jan 22, 2021 at 15:43

5 Answers 5

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multi-user.target means that the systemd-service will start when the system reach runlevel 2.

To complement the answer, here's a table of the targets and their run levels:

Run Lvl Target Units Description 0 runlevel0.target, poweroff.target Shut down and power off 1 runlevel1.target, rescue.target Set up a rescue shell 2,3,4 runlevel[234].target, Set up a non-gfx multi-user shell multi-user.target 5 runlevel5.target, graphical.target Set up a gfx multi-user shell 6 runlevel6.target, reboot.target Shut down and reboot the system
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    But it's WantedBy=multi-user.target, so it just means the service will start and before runlevel 2 right ? not necessarily when system reaches runlevel 2, am I wrong ? Commented Dec 10, 2018 at 17:53
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    What's a gfx multi-user shell? Any reference? Commented Oct 14, 2019 at 7:46
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    A gfx multi-user shell refer to a multi-user system with a GUI. Commented Oct 15, 2019 at 14:44
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    @TobiasHolm You might not be completely right, I'm getting the same target (graphical.target) even on a GUI-less Debian server with systemctl get-default. Commented Nov 27, 2021 at 10:30
  • FYI, see also man systemd.special and man runlevel. Commented Jan 17, 2024 at 8:32
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This is the dependencies handling mechanism in Systemd.
multi-user.target is the alternative for runlevel 3 in SystemV world.

That said, reaching multi-user.target includes starting the Confluent ZooKeeper service.

That's probably what you need indeed.

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    pretty vague answer. amazed that it got the green tick. some people be like, knows a little, throws a brittle. Commented Aug 21, 2021 at 5:14
  • actually, it's pretty informative even for systemd disliking person - if one is not ready to grasp content, they shall start learning from scratch. Commented Feb 26, 2023 at 8:46
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I found this landoflinux.com tutorial (webarchive) the simplest to understand. You can run the following command yourself to see what's there:

$ ls -al /lib/systemd/system/runlevel* lrwxrwxrwx. 1 root root 15 Apr 25 10:31 /lib/systemd/system/runlevel0.target -> poweroff.target lrwxrwxrwx. 1 root root 13 Apr 25 10:31 /lib/systemd/system/runlevel1.target -> rescue.target lrwxrwxrwx. 1 root root 17 Apr 25 10:31 /lib/systemd/system/runlevel2.target -> multi-user.target lrwxrwxrwx. 1 root root 17 Apr 25 10:31 /lib/systemd/system/runlevel3.target -> multi-user.target lrwxrwxrwx. 1 root root 17 Apr 25 10:31 /lib/systemd/system/runlevel4.target -> multi-user.target lrwxrwxrwx. 1 root root 16 Apr 25 10:31 /lib/systemd/system/runlevel5.target -> graphical.target lrwxrwxrwx. 1 root root 13 Apr 25 10:31 /lib/systemd/system/runlevel6.target -> reboot.target

But you should probably just read the linked question accepted answer about targets.

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    "landoflinux.com" is now a gambling site. Commented May 1 at 4:44
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    @user5359531 cheers - used the archive link Commented May 18 at 18:44
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tldr if a service is wanted by multi-user.target, the service requires a number of services needed for a non-graphical multi-user session to be started (see the required services in the chart below).

$ man systemd.special ... multi-user.target A special target unit for setting up a multi-user system (non-graphical). This is pulled in by graphical.target. Units that are needed for a multi-user system shall add Wants= dependencies for their unit to this unit during installation. This is best configured via WantedBy=multi-user.target in the unit's [Install] section. ...

the services required by the target can be found in the chart below:

 cryptsetup-pre.target veritysetup-pre.target | (various low-level v API VFS mounts: (various cryptsetup/veritysetup devices...) mqueue, configfs, | | debugfs, ...) v | | cryptsetup.target | | (various swap | | remote-fs-pre.target | devices...) | | | | | | | | | v | v local-fs-pre.target | | | (network file systems) | swap.target | | v v | | | v | remote-cryptsetup.target | | | (various low-level (various mounts and | remote-veritysetup.target | | | services: udevd, fsck services...) | | | | | tmpfiles, random | | | remote-fs.target | | seed, sysctl, ...) v | | | | | | local-fs.target | | _____________/ | | | | | |/ \____|______|_______________ ______|___________/ | \ / | v | sysinit.target | | | ______________________/|\_____________________ | / | | | \ | | | | | | | v v | v | | (various (various | (various | | timers...) paths...) | sockets...) | | | | | | | | v v | v | | timers.target paths.target | sockets.target | | | | | | v | v \_______ | _____/ rescue.service | \|/ | | v v | basic.target rescue.target | | | ________v____________________ | / | \ | | | | | v v v | display- (various system (various system | manager.service services services) | | required for | | | graphical UIs) v v | | multi-user.target emergency.service | | | | \_____________ | _____________/ v \|/ emergency.target v graphical.target

source

the list of dependencies can also be found with

$ systemctl list-dependencies multi-user.target
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TL;DR

multiuser.target is a system setting based terminal only meant for use on systems that do not have or require a graphical desktop environment. Such as for instance, a cluster.

The reference to runlevels is not really relevant, as they are not part of systemd. They are a set of system configurations (in this case 3 different ones) that you can use to determine which services will be started and which not.

But the short answer to your question is: multiuser.target is a special system configuration for a shell-only environment on multi-user systems that can be called at startup (or whenever you want, actually)/

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