def _new_best_path(self, new_best_path):
old_best_path = self._best_path
self._best_path = new_best_path
LOG.debug('New best path selected for destination %s' % (self))
# If old best path was withdrawn
if (old_best_path and old_best_path not in self._known_path_list
and self._sent_routes):
# Have to clear sent_route list for this destination as
# best path is removed.
self._sent_routes = {}
# Communicate that we have new best path to all qualifying
# bgp-peers.
pm = self._core_service.peer_manager
pm.comm_new_best_to_bgp_peers(new_best_path)
# withdraw old best path
if old_best_path and self._sent_routes:
for sent_route in self._sent_routes.values():
sent_path = sent_route.path
withdraw_clone = sent_path.clone(for_withdrawal=True)
outgoing_route = OutgoingRoute(withdraw_clone)
sent_route.sent_peer.enque_outgoing_msg(outgoing_route)
LOG.debug('Sending withdrawal to %s for %s' %
(sent_route.sent_peer, outgoing_route))
self._sent_routes = {}
def _best_path_lost(self):
self._best_path = None
if self._sent_routes:
# We have to send update-withdraw to all peers to whom old best
# path was sent.
for sent_route in self._sent_routes.values():
sent_path = sent_route.path
withdraw_clone = sent_path.clone(for_withdrawal=True)
outgoing_route = OutgoingRoute(withdraw_clone)
sent_route.sent_peer.enque_outgoing_msg(outgoing_route)
LOG.debug('Sending withdrawal to %s for %s' %
(sent_route.sent_peer, outgoing_route))
# Have to clear sent_route list for this destination as
# best path is removed.
self._sent_routes = {}
def resend_sent(self, route_family, peer):
"""For given `peer` re-send sent paths.
Parameters:
- `route-family`: (RouteFamily) of the sent paths to re-send
- `peer`: (Peer) peer for which we need to re-send sent paths
"""
if peer not in self._peers.values():
raise ValueError('Could not find given peer (%s)' % peer)
if route_family not in SUPPORTED_GLOBAL_RF:
raise ValueError(
'Given route family (%s) is not supported.' % route_family
)
# Iterate over the global table for given afi, safi and enqueue
# out-going routes.
table = self._table_manager.get_global_table_by_route_family(
route_family
)
for destination in table.itervalues():
# Check if this destination's sent - routes include this peer.
# i.e. check if this destinations was advertised and enqueue
# the path only if it was. If the current best-path has not been
# advertised before, it might already have a OutgoingRoute queued
# to be sent to the peer.
sent_routes = destination.sent_routes
if sent_routes is None or len(sent_routes) == 0:
continue
for sent_route in sent_routes:
if sent_route.sent_peer == peer:
# update med - if previously med was set per neighbor or
# wasn't set at all now it could have changed and we may
# need to set new value there
p = sent_route.path
if p.med_set_by_target_neighbor or p.get_pattr(
BGP_ATTR_TYPE_MULTI_EXIT_DISC) is None:
sent_route.path = \
clone_path_and_update_med_for_target_neighbor(
sent_route.path, peer.med
)
ogr = OutgoingRoute(sent_route.path,
for_route_refresh=True)
peer.enque_outgoing_msg(ogr)
def withdraw_if_sent_to(self, peer):
"""Sends a withdraw for this destination to given `peer`.
Check the records if we indeed advertise this destination to given peer
and if so, creates a withdraw for advertised route and sends it to the
peer.
Parameter:
- `peer`: (Peer) peer to send withdraw to
"""
from ryu.services.protocols.bgp.peer import Peer
if not isinstance(peer, Peer):
raise TypeError('Currently we only support sending withdrawal'
' to instance of peer')
sent_route = self._sent_routes.pop(peer, None)
if not sent_route:
return False
sent_path = sent_route.path
withdraw_clone = sent_path.clone(for_withdrawal=True)
outgoing_route = OutgoingRoute(withdraw_clone)
sent_route.sent_peer.enque_outgoing_msg(outgoing_route)
return True
