nixpkgs/nixos/modules/system
Jamey Sharp 8d40083690 nixos/stage-2: create empty machine-id at boot
Previously, the activation script was responsible for ensuring that
/etc/machine-id exists. However, the only time it could not already
exist is during stage-2-init, not while switching configurations,
because one of the first things systemd does when starting up as PID 1
is to create this file. So I've moved the initialization to
stage-2-init.

Furthermore, since systemd will do the equivalent of
systemd-machine-id-setup if /etc/machine-id doesn't have valid contents,
we don't need to do that ourselves.

We _do_, however, want to ensure that the file at least exists, because
systemd also uses the non-existence of this file to guess that this is a
first-boot situation. In that case, systemd tries to create some
symlinks in /etc/systemd/system according to its presets, which it can't
do because we've already populated /etc according to the current NixOS
configuration.

This is not necessary for any other activation script snippets, so it's
okay to do it after stage-2-init runs the activation script. None of
them declare a dependency on the "systemd" snippet. Also, most of them
only create files or directories in ways that obviously don't need the
machine-id set.
2018-09-30 10:45:35 -07:00
..
activation nixos: top-level: indent 2018-09-24 19:45:16 +00:00
boot nixos/stage-2: create empty machine-id at boot 2018-09-30 10:45:35 -07:00
etc environment.etc: add user/group option 2017-07-29 23:56:46 +01:00