Systemd USE flag transition and OpenRC script coexistence

Direct Answer

Gentoo does not provide a deterministic priority mechanism that automatically suppresses an OpenRC script when a systemd unit is installed, or vice versa. File coexistence under /etc/init.d and /usr/lib/systemd/system does not confer authority to either init system. Runtime authority is determined solely by which init system is running as PID 1 and by the enablement state of the service within that init system.

Confirmed Facts vs. Likely Explanation

Confirmed: During a normal boot, only one init system runs as PID 1. The systemd USE flag controls whether Portage installs systemd unit files; it does not remove or disable OpenRC init scripts. Depending on the ebuild, OpenRC scripts may be installed independently of the openrc USE flag or through service dependencies. Because both file sets can be present on disk, the filesystem alone cannot tell you which init system is managing a daemon. systemd's internal unit precedence applies only within systemd, not against OpenRC.

Likely explanation: If systemd is PID 1, OpenRC scripts are inert unless explicitly executed or unless OpenRC tooling is still configured to manage runlevels. However, this is a runtime state, not a packaging guarantee. You should not assume an installed OpenRC script is inactive merely because systemd is the active init.

Verification Steps

To confirm that a package is exclusively using the systemd unit, verify the init authority and then inspect both init systems' state for the specific service.

1. Confirm which init is PID 1:

   ps -p 1 -o comm=

2. Check the systemd unit state (replace UNIT with the actual unit name, e.g., sshd.service):

   systemctl is-enabled UNIT
   systemctl is-active UNIT
   systemctl status UNIT

   The status load path should reference a systemd unit directory rather than /etc/init.d.
3. Verify OpenRC is not managing the service. If OpenRC tooling is present, check runlevel membership and current state:

   rc-update show
   rc-status

   The service should not appear in boot, default, or nonetwork runlevels.
4. Inspect installed compile-time flags for context, but treat this as build metadata, not runtime proof:

   equery uses CATEGORY/PACKAGE

   Expect systemd enabled and openrc disabled, then correlate with the runtime checks above.

Caveats

• Confirm the exact unit name and aliases. systemctl status can display drop-ins or alias units that shadow the package's unit file.
• Gentoo is a rolling distribution; profile defaults and ebuild behavior change. Verify against the target profile and package version rather than relying on general behavior.
• An installed OpenRC script is not automatically inactive. If rc-update show lists the service in a runlevel, OpenRC may still attempt to start it during boot.

Missing Diagnostic

Provide the package atom or the exact systemd unit name. If OpenRC is PID 1, or if the unit name is unknown, the verification steps change.