Systemd

Configuration

Services can be added by adding a services.systemd section to a host config, a trait config or a folder’s dir.yml. For example:

# Services that should be enabled when this trait is enabled.
services:
  systemd:
    - systemd-timesyncd
    - backup.timer

All systemd services that’re defined in the host config, in the configs of enabled traits and in dir.yml files will then be enabled for the given host.

Unit names without an explicit unit suffix (such as .service or .timer) refer to .service units, just like they do when calling systemctl. I.e. systemd-timesyncd and systemd-timesyncd.service are treated as the same unit.

User and System Mode

Depending on the current mode bois runs in, different systemd units are targeted:

• In System mode, the system’s systemd instance is managed.
• In User mode, all systemctl calls are made with the --user flag, so the user’s own systemd instance is managed instead. Unit files for user services live in directories such as ~/.config/systemd/user/.

Deployment

Services are enabled at the very end of a deployment, after packages have been installed and files have been deployed. That way, unit files that’re installed by packages or deployed by bois itself already exist by the time they’re enabled.

Services are only enabled (e.g. systemctl enable myunit), not started. If a service should be started right away at the moment it gets enabled, use the explicit declaration syntax:

services:
  systemd:
    - name: docker
      start: true

This enables the unit via systemctl enable --now.

Note that the start flag only takes effect at the moment the service gets enabled. Bois doesn’t manage the running state of services. This means that a service that’s already enabled but was stopped manually won’t be started again on the next deployment.

Cleanup

Once a service is removed from the configuration, it’s stopped and disabled (systemctl disable --now) during the cleanup phase of the next deployment.

Services are cleaned up before files and packages are removed, while the service’s unit files still exist on the system.