'Perform FDB Agent Extension initialization.'

def initialize(self, connection, driver_type):

    valid_driver_types = (linux_bridge_constants.EXTENSION_DRIVER_TYPE, ovs_constants.EXTENSION_DRIVER_TYPE)
    if (driver_type not in valid_driver_types):
        LOG.error(_LE('FDB    extension    is    only    supported    for    OVS    and    linux    bridge    agent,    currently    uses    %(driver_type)s'), {'driver_type': driver_type})
        sys.exit(1)
    self.device_mappings = helpers.parse_mappings(cfg.CONF.FDB.shared_physical_device_mappings, unique_keys=False)
    devices = self._get_devices()
    if (not devices):
        LOG.error(_LE('Invalid    configuration    provided    for    FDB    extension:    no    physical    devices'))
        sys.exit(1)
    self.fdb_tracker = self.FdbTableTracker(devices)
