Running agetty on ttyS0 interferes with the backdoor, which uses ttyS0
as its standard error. After agetty starts, writes to the stderr file
descriptor will return EIO (though doing "exec 2>/proc/self/fd/2" will
miracuously fix this).
http://hydra.nixos.org/build/3252782
The triggers are just arbitrary strings that are included in the unit
under X-Restart-Triggers. The idea is that if they change between
reconfigurations, switch-to-configuration will restart the unit
because its store path changed. This is mostly useful for services
that implicitly depend on generated files in /etc. Thus you can say
restartTriggers = [ confFile ];
where ‘confFile’ is the derivation that generated the /etc file in
question.
So instead of:
boot.systemd.services."foo".serviceConfig =
''
StartLimitInterval=10
CPUShare=500
'';
you can say:
boot.systemd.services."foo".serviceConfig.StartLimitInterval = 10;
boot.systemd.services."foo".serviceConfig.CPUShare = 500;
This way all unit options are available and users can set/override
options in configuration.nix.
