start peering connection to neighbors from node's advertise-ip

Author: tamihiro

pkg/controllers/routing/bgp_peers.go

@@ -91,13 +91,18 @@ func (nrc *NetworkRoutingController) syncInternalPeers() {
 
 		currentNodes = append(currentNodes, nodeIP.String())
 		nrc.activeNodes[nodeIP.String()] = true
+		// explicitly set neighbors.transport.config.local-address with nodeIP which is configured
+		// as their neighbor address at the remote peers.
+		// this prevents the controller from initiating connection to its peers with a different IP address
+		// when multiple L3 interfaces are active.
 		n := &gobgpapi.Peer{
 			Conf: &gobgpapi.PeerConf{
 				NeighborAddress: nodeIP.String(),
 				PeerAs:          nrc.nodeAsnNumber,
 			},
 			Transport: &gobgpapi.Transport{
-				RemotePort: nrc.bgpPort,
+				LocalAddress: nrc.nodeIP.String(),
+				RemotePort:   nrc.bgpPort,
 			},
 		}
 
@@ -238,8 +243,8 @@ func connectToExternalBGPPeers(server *gobgp.BgpServer, peerNeighbors []*gobgpap
 }
 
 // Does validation and returns neighbor configs
-func newGlobalPeers(ips []net.IP, ports []uint32, asns []uint32, passwords []string, holdtime float64) (
-	[]*gobgpapi.Peer, error) {
+func newGlobalPeers(ips []net.IP, ports []uint32, asns []uint32, passwords []string, holdtime float64,
+	localAddress string) ([]*gobgpapi.Peer, error) {
 	peers := make([]*gobgpapi.Peer, 0)
 
 	// Validations
@@ -269,14 +274,19 @@ func newGlobalPeers(ips []net.IP, ports []uint32, asns []uint32, passwords []str
 				asns[i])
 		}
 
+		// explicitly set neighbors.transport.config.local-address with nodeIP which is configured
+		// as their neighbor address at the remote peers.
+		// this prevents the controller from initiating connection to its peers with a different IP address
+		// when multiple L3 interfaces are active.
 		peer := &gobgpapi.Peer{
 			Conf: &gobgpapi.PeerConf{
 				NeighborAddress: ips[i].String(),
 				PeerAs:          asns[i],
 			},
 			Timers: &gobgpapi.Timers{Config: &gobgpapi.TimersConfig{HoldTime: uint64(holdtime)}},
 			Transport: &gobgpapi.Transport{
-				RemotePort: options.DefaultBgpPort,
+				LocalAddress: localAddress,
+				RemotePort:   options.DefaultBgpPort,
 			},
 		}
 

pkg/controllers/routing/network_routes_controller.go

@@ -1088,7 +1088,8 @@ func (nrc *NetworkRoutingController) startBgpServer(grpcServer bool) error {
 		}
 
 		// Create and set Global Peer Router complete configs
-		nrc.globalPeerRouters, err = newGlobalPeers(peerIPs, peerPorts, peerASNs, peerPasswords, nrc.bgpHoldtime)
+		nrc.globalPeerRouters, err = newGlobalPeers(peerIPs, peerPorts, peerASNs, peerPasswords, nrc.bgpHoldtime,
+			nrc.nodeIP.String())
 		if err != nil {
 			err2 := nrc.bgpServer.StopBgp(context.Background(), &gobgpapi.StopBgpRequest{})
 			if err2 != nil {
@@ -1281,8 +1282,8 @@ func NewNetworkRoutingController(clientset kubernetes.Interface,
 		}
 	}
 
-	nrc.globalPeerRouters, err = newGlobalPeers(kubeRouterConfig.PeerRouters, peerPorts, peerASNs,
-		peerPasswords, nrc.bgpHoldtime)
+	nrc.globalPeerRouters, err = newGlobalPeers(kubeRouterConfig.PeerRouters, peerPorts,
+		peerASNs, peerPasswords, nrc.bgpHoldtime, nrc.nodeIP.String())
 	if err != nil {
 		return nil, fmt.Errorf("error processing Global Peer Router configs: %s", err)
 	}