'Fanout the information to all L3 agents.
This function will fanout the router_id or ext_net_id
to the L3 Agents.'

def _notification_fanout(self, context, method, router_id=None, **kwargs):

    ext_net_id = kwargs.get('ext_net_id')
    if router_id:
        kwargs['router_id'] = router_id
        LOG.debug('Fanout    notify    agent    at    %(topic)s    the    message    %(method)s    on    router    %(router_id)s', {'topic': topics.L3_AGENT, 'method': method, 'router_id': router_id})
    if ext_net_id:
        LOG.debug('Fanout    notify    agent    at    %(topic)s    the    message    %(method)s    for    external_network        %(ext_net_id)s', {'topic': topics.L3_AGENT, 'method': method, 'ext_net_id': ext_net_id})
    cctxt = self.client.prepare(fanout=True)
    cctxt.cast(context, method, **kwargs)
