Merge pull request #117371 from grahamc/sysctl-hostname

    # Set the host and domain names in the activation script.  Don't

    # clear it if it's not configured in the NixOS configuration,

    # since it may have been set by dhcpcd in the meantime.

    system.activationScripts.hostname =

      optionalString (cfg.hostName != "") ''

        hostname "${cfg.hostName}"

    system.activationScripts.hostname = let

        effectiveHostname = config.boot.kernel.sysctl."kernel.hostname" or cfg.hostName;

      in optionalString (effectiveHostname != "") ''

        hostname "${effectiveHostname}"

      '';

    system.activationScripts.domain =

      optionalString (cfg.domain != null) ''