[systemd-devel] Minimal systemd configuration

[Lennart Poettering]

On Sun, 05.04.15 09:56, sdrb (sdrb at onet.eu) wrote:

> Hello,
> 
> I've got a few very basic questions regarding configuration of systemd.
> 
> I'm trying to setup some minimal configuration for qemu running linux.
> 
> The qemu runs linux kernel which mounts nfs-root as root directory.
> I've made minimal nfs-root and now I'd like to start the system with systemd
> in it.
> I copied all the files from /usr/lib/systemd and /etc/systemd from my linux
> to nfs-root but when linux runs systemd - I got a lot of error messages like
> "[FAILED] Failed to start xxx service".
> 
> My questions are:
> 
> 1. Is there any documentation for creating minimal systemd configuration? I
> mean for example - for qemu or embedded systems - with only sshd daemon
> running and console to just log into the system?

Use ./configure's various --disable switches to disable everything you
don't want.

> 2. Does the systemd require external applications like mount, login or other
> to work properly?

Yes, things like mount are strictly necessary, see the README for a
list of required dependencies.

> 3. Is it possible to reconfigure systemd to run some script at the end of
> initialisation?

No. This concept is not supported, because "end of initialization" is
very vague, conceptionally questionnable, and unclear if people want
to run multiple services like this...

Lennart

-- 
Lennart Poettering, Red Hat