[muxorch] Fixing bug with updateRoute and mux neighbors (sonic-net#3187)

* [muxorch] Fixing bug with updateRoute and mux neighbors

mux neighbors that were not the configured mux ip were being treated as active.
bug was causing crash when neighbor was not the same as the mux configured neighbor

orchagent/muxorch.cpp

@@ -1283,14 +1283,12 @@ void MuxOrch::updateRoute(const IpPrefix &pfx, bool add)
     for (auto it = nextHops.begin(); it != nextHops.end(); it++)
     {
         NextHopKey nexthop = *it;
-        /* This will only work for configured MUX neighbors (most cases)
-         * TODO: add way to find MUX from neighbor
-         */
-        MuxCable* cable = findMuxCableInSubnet(nexthop.ip_address);
-        auto standalone = standalone_tunnel_neighbors_.find(nexthop.ip_address);
+        NeighborEntry neighbor;
+        MacAddress mac;
+
+        gNeighOrch->getNeighborEntry(nexthop, neighbor, mac);
 
-        if ((cable == nullptr && standalone == standalone_tunnel_neighbors_.end()) ||
-             cable->isActive())
+        if (isNeighborActive(neighbor.ip_address, mac, neighbor.alias))
         {
             /* Here we pull from local nexthop ID because neighbor update occurs during state change
              * before nexthopID is updated in neighorch. This ensures that if a neighbor is Active
@@ -1302,11 +1300,11 @@ void MuxOrch::updateRoute(const IpPrefix &pfx, bool add)
             if (status != SAI_STATUS_SUCCESS)
             {
                 SWSS_LOG_ERROR("Failed to set route entry %s to nexthop %s",
-                        pfx.to_string().c_str(), nexthop.to_string().c_str());
+                        pfx.to_string().c_str(), neighbor.to_string().c_str());
                 continue;
             }
             SWSS_LOG_NOTICE("setting route %s with nexthop %s %" PRIx64 "",
-                pfx.to_string().c_str(), nexthop.to_string().c_str(), next_hop_id);
+                pfx.to_string().c_str(), neighbor.to_string().c_str(), next_hop_id);
             active_found = true;
             break;
         }

tests/test_mux.py

@@ -794,6 +794,8 @@ def create_and_test_multi_nexthop_routes(self, dvs, dvs_route, appdb, macs, new_
         new_ipv6_nexthop = self.SERV3_IPV6
         non_mux_ipv4 = "11.11.11.11"
         non_mux_ipv6 = "2222::100"
+        mux_neighbor_ipv4 = "192.170.0.100"
+        mux_neighbor_ipv6 = "fc02:1000:100::100"
         non_mux_mac = "00:aa:aa:aa:aa:aa"
         mux_ports = ["Ethernet0", "Ethernet4"]
         new_mux_port = "Ethernet8"
@@ -806,6 +808,8 @@ def create_and_test_multi_nexthop_routes(self, dvs, dvs_route, appdb, macs, new_
         self.add_neighbor(dvs, new_ipv6_nexthop, new_mac)
         self.add_neighbor(dvs, non_mux_ipv4, non_mux_mac)
         self.add_neighbor(dvs, non_mux_ipv6, non_mux_mac)
+        self.add_neighbor(dvs, mux_neighbor_ipv4, macs[1])
+        self.add_neighbor(dvs, mux_neighbor_ipv6, macs[1])
 
         for port in mux_ports:
             self.set_mux_state(appdb, port, ACTIVE)
@@ -826,6 +830,14 @@ def create_and_test_multi_nexthop_routes(self, dvs, dvs_route, appdb, macs, new_
             self.multi_nexthop_test_route_update_decrease_size(appdb, asicdb, dvs, dvs_route, route_ipv4, mux_ports, ipv4_nexthops, non_mux_nexthop=non_mux_ipv4)
             self.multi_nexthop_test_route_update_decrease_size(appdb, asicdb, dvs, dvs_route, route_ipv6, mux_ports, ipv6_nexthops, non_mux_nexthop=non_mux_ipv6)
 
+            # Testing mux neighbors that do not match mux configured ip
+            self.add_route(dvs, route_ipv4, [self.SERV1_IPV4, mux_neighbor_ipv4])
+            self.add_route(dvs, route_ipv6, [self.SERV1_IPV6, mux_neighbor_ipv6])
+            self.multi_nexthop_test_toggle(appdb, asicdb, dvs_route, route_ipv4, mux_ports, [self.SERV1_IPV4, mux_neighbor_ipv4])
+            self.multi_nexthop_test_toggle(appdb, asicdb, dvs_route, route_ipv6, mux_ports, [self.SERV1_IPV6, mux_neighbor_ipv6])
+            self.del_route(dvs,route_ipv4)
+            self.del_route(dvs,route_ipv6)
+
             # # These tests do not create route, so create beforehand:
             self.add_route(dvs, route_ipv4, ipv4_nexthops)
             self.add_route(dvs, route_ipv6, ipv6_nexthops)
@@ -850,6 +862,8 @@ def create_and_test_multi_nexthop_routes(self, dvs, dvs_route, appdb, macs, new_
                 self.del_neighbor(dvs, neighbor)
             self.del_neighbor(dvs, new_ipv4_nexthop)
             self.del_neighbor(dvs, new_ipv6_nexthop)
+            self.del_neighbor(dvs, mux_neighbor_ipv4)
+            self.del_neighbor(dvs, mux_neighbor_ipv6)
 
     def create_and_test_NH_routes(self, appdb, asicdb, dvs, dvs_route, mac):
         '''