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# systemd/FAQ

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## FAQ

For an up-to-date list of known issues, look at the upstream TODO.

### Why do I get log messages on my console?

You must set the kernel loglevel yourself. Historically, `/etc/rc.sysinit` did this for us and set dmesg's loglevel to `3`, which was a reasonably quiet loglevel. Either add `loglevel=3` or `quiet` to your kernel parameters.

### How do I change the default number of gettys?

Currently, only one getty is launched by default. If you switch to another TTY, a getty will be launched there (socket-activation style). In other words, `Ctl+Alt+F2` will launch a new getty on tty2.

By default, the number of auto-activated gettys is capped at six. Thus `F7` through `F12` will not launch a getty.

If you want to change this behavior, then edit `/etc/systemd/logind.conf` and change the value of `NAutoVTs`. If you want all `Fx` keys to start a getty, increase the value of `NAutoVTs` to `12`. If you are forwarding journald to tty12, increase the value of `NAutoVTs` to `11` (thus leaving tty12 free).

You can also pre-activate gettys which will be running from boot.

To add another pre-activated getty, enable and start `getty@ttyX.service`.

To remove a getty, disable and stop the relevant `getty@ttyX.service`.

systemd does not use the `/etc/inittab` file.

### How do I get more verbose output during boot?

If you see no output at all in console after the initram message, this means you have the `quiet` parameter in your kernel line. It is best to remove it, at least the first time you boot with systemd, to see if everything is ok. Then, you will see a list `[ OK ]` in green or `[ FAILED ]` in red.

Any messages are logged to the system log and if you want to find out about the status of your system, use systemctl or look at the boot/system log with journalctl.

### How do I avoid clearing the console after boot?

Create a directory called `/etc/systemd/system/getty@.service.d` and place `nodisallocate.conf` in there to override the `TTYVTDisallocate` option to `no`.

    /etc/systemd/system/getty@.service.d/nodisallocate.conf

    [Service]
    TTYVTDisallocate=no

### What kernel options are required for systemd?

Kernels prior to 3.0 are unsupported.

If you use a custom kernel, you will need to make sure that systemd's options are selected.

If you are compiling a new kernel for use with an installed version of systemd, the required and recommended options are listed in the systemd README file `/usr/share/doc/systemd/README`.

If you are preparing to install a new version of systemd and are running a custom kernel, the most recent version of the file can be found in the systemd GitHub repository.

### What other units does a unit depend on?

For example, if you want to figure out which services a target like `multi-user.target` pulls in, use something like this:

    $ systemctl show -p "Wants" multi-user.target

    Wants=rc-local.service avahi-daemon.service rpcbind.service NetworkManager.service acpid.service dbus.service atd.service crond.service auditd.service ntpd.service udisks.service bluetooth.service org.cups.cupsd.service wpa_supplicant.service getty.target modem-manager.service portreserve.service abrtd.service yum-updatesd.service upowerd.service test-first.service pcscd.service rsyslog.service haldaemon.service remote-fs.target plymouth-quit.service systemd-update-utmp-runlevel.service sendmail.service lvm2-monitor.service cpuspeed.service udev-post.service mdmonitor.service iscsid.service livesys.service livesys-late.service irqbalance.service iscsi.service

Instead of `Wants` you might also try `WantedBy`, `Requires`, `RequiredBy`, `Conflicts`, `ConflictedBy`, `Before`, `After` for the respective types of dependencies and their inverse.

### My computer shuts down, but the power stays on

Use `systemctl poweroff` instead of `systemctl halt`.

### How can I make a script start during the boot process?

Create a new file as `/etc/systemd/system/myscript.service` and add the following contents:

    /etc/systemd/system/myscript.service

    [Unit]
    Description=My script

    [Service]
    ExecStart=/usr/bin/my-script

    [Install]
    WantedBy=multi-user.target

This example assumes you want your script to start up when the target multi-user is launched. Make sure the script is executable.

Enable `myscript.service` to start the service at boot.

Note: In case you want to start a shell script, make sure you have `#!/bin/sh` in the first line of the script. Do not write something like `ExecStart=/bin/sh /path/to/script.sh` because that will not work.

### Service unit active state is "active (exited)" in green

This is the expected behaviour for oneshot services that also use `RemainAfterExit=yes`. See systemd.service(5) § OPTIONS for more information. Some examples of oneshot services that behave this way are `systemd-user-sessions.services`, `nftables.service`, and `iptables.service`.

### Failure to enable unit due to preexisting symlink

You may encounter the following error when attempting to enable a unit:

    Failed to enable unit: File /etc/systemd/system/symlink already exists and is a symlink to file.

This can occur when the `symlink` created by enabling a unit already exists in `/etc/systemd/system/`. This typically happens when switching from one display manager to another one (for instance GDM to SDDM, which can be enabled with `gdm.service` and `sddm.service`, respectively) and the corresponding symlink `/etc/systemd/system/display-manager.service` already exists.

To solve this problem, either first disable the relevant display manager before enabling the new one, or use the `-f`/`--force` option when enabling the new one to overwrite any existing conflicting symlinks (per systemctl(1) § OPTIONS).

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- Init