[systemd-devel] How to run *ctl command using systemd-nspawn

[Koen Kooi]

Hi,

To help with flashing the onboard eMMC of a 100000 boards I'm using systemd-nspawn to run package postinstall scripts that generate UUIDs and some other things and it's working great for that! Every board now has a unique value in /etc/machine-id instead it being empty and systemd randomizing it on startup.

What doesn't work however is something like this:

	systemd-nspawn -D ${PART2MOUNT} /usr/bin/timedatectl set-timezone Europe/Paris

or this:

	systemd-nspawn -D ${PART2MOUNT} /usr/bin/hostnamectl set-hostname BeagleBoneBlack

I know I can run the lowlevel 'ln -sf <zoneinfo> /etc/timezone' or echo the name into /etc/hostname, but I'd like to use the *ctl commands because they work and have error handling built-in. 
it looks like I would need -b to get the *ctl commands to work, but -b doesn't support running single commands and exiting.

My goal is to be able to drop in a rootfs tarball and change timezone and hostname settings in a config file for the flasher script and avoid generating N different tarballs. For use in the office lab I use something like [1] to generate the hostnames based on board revision and serial number.

So, is there a way to *ctl command using systemd-nspawn in a rootfs that wasn't specially prepared (e.g. helper units/targets) for that?

regards,

Koen

[1] https://plus.google.com/100242854243155306943/posts/ddoZgvLnixa