Overlay fix for transient IP reuse

drivers/overlay/encryption.go

@@ -21,7 +21,6 @@ import (
 
 const (
 	r            = 0xD0C4E3
-	timeout      = 30
 	pktExpansion = 26 // SPI(4) + SeqN(4) + IV(8) + PadLength(1) + NextHeader(1) + ICV(8)
 )
 

drivers/overlay/joinleave.go

@@ -68,7 +68,7 @@ func (d *driver) Join(nid, eid string, sboxKey string, jinfo driverapi.JoinInfo,
 
 	ep.ifName = containerIfName
 
-	if err := d.writeEndpointToStore(ep); err != nil {
+	if err = d.writeEndpointToStore(ep); err != nil {
 		return fmt.Errorf("failed to update overlay endpoint %s to local data store: %v", ep.id[0:7], err)
 	}
 
@@ -86,7 +86,7 @@ func (d *driver) Join(nid, eid string, sboxKey string, jinfo driverapi.JoinInfo,
 		return err
 	}
 
-	if err := sbox.AddInterface(overlayIfName, "veth",
+	if err = sbox.AddInterface(overlayIfName, "veth",
 		sbox.InterfaceOptions().Master(s.brName)); err != nil {
 		return fmt.Errorf("could not add veth pair inside the network sandbox: %v", err)
 	}
@@ -100,15 +100,15 @@ func (d *driver) Join(nid, eid string, sboxKey string, jinfo driverapi.JoinInfo,
 		return err
 	}
 
-	if err := nlh.LinkSetHardwareAddr(veth, ep.mac); err != nil {
+	if err = nlh.LinkSetHardwareAddr(veth, ep.mac); err != nil {
 		return fmt.Errorf("could not set mac address (%v) to the container interface: %v", ep.mac, err)
 	}
 
 	for _, sub := range n.subnets {
 		if sub == s {
 			continue
 		}
-		if err := jinfo.AddStaticRoute(sub.subnetIP, types.NEXTHOP, s.gwIP.IP); err != nil {
+		if err = jinfo.AddStaticRoute(sub.subnetIP, types.NEXTHOP, s.gwIP.IP); err != nil {
 			logrus.Errorf("Adding subnet %s static route in network %q failed\n", s.subnetIP, n.id)
 		}
 	}
@@ -122,7 +122,7 @@ func (d *driver) Join(nid, eid string, sboxKey string, jinfo driverapi.JoinInfo,
 
 	d.peerAdd(nid, eid, ep.addr.IP, ep.addr.Mask, ep.mac, net.ParseIP(d.advertiseAddress), false, false, true)
 
-	if err := d.checkEncryption(nid, nil, n.vxlanID(s), true, true); err != nil {
+	if err = d.checkEncryption(nid, nil, n.vxlanID(s), true, true); err != nil {
 		logrus.Warn(err)
 	}
 
@@ -200,7 +200,7 @@ func (d *driver) EventNotify(etype driverapi.EventType, nid, tableName, key stri
 	}
 
 	if etype == driverapi.Delete {
-		d.peerDelete(nid, eid, addr.IP, addr.Mask, mac, vtep)
+		d.peerDelete(nid, eid, addr.IP, addr.Mask, mac, vtep, false)
 		return
 	}
 
@@ -232,11 +232,9 @@ func (d *driver) Leave(nid, eid string) error {
 		}
 	}
 
-	n.leaveSandbox()
+	d.peerDelete(nid, eid, ep.addr.IP, ep.addr.Mask, ep.mac, net.ParseIP(d.advertiseAddress), true)
 
-	if err := d.checkEncryption(nid, nil, 0, true, false); err != nil {
-		logrus.Warn(err)
-	}
+	n.leaveSandbox()
 
 	return nil
 }

drivers/overlay/ov_network.go

@@ -251,8 +251,9 @@ func (d *driver) DeleteNetwork(nid string) error {
 		if err := d.deleteEndpointFromStore(ep); err != nil {
 			logrus.Warnf("Failed to delete overlay endpoint %s from local store: %v", ep.id[0:7], err)
 		}
-
 	}
+	// flush the peerDB entries
+	d.peerFlush(nid)
 	d.deleteNetwork(nid)
 
 	vnis, err := n.releaseVxlanID()
@@ -505,11 +506,7 @@ func (n *network) restoreSubnetSandbox(s *subnet, brName, vxlanName string) erro
 	vxlanIfaceOption := make([]osl.IfaceOption, 1)
 	vxlanIfaceOption = append(vxlanIfaceOption, sbox.InterfaceOptions().Master(brName))
 	Ifaces[vxlanName+"+vxlan"] = vxlanIfaceOption
-	err = sbox.Restore(Ifaces, nil, nil, nil)
-	if err != nil {
-		return err
-	}
-	return nil
+	return sbox.Restore(Ifaces, nil, nil, nil)
 }
 
 func (n *network) setupSubnetSandbox(s *subnet, brName, vxlanName string) error {
@@ -760,58 +757,38 @@ func (n *network) watchMiss(nlSock *nl.NetlinkSocket) {
 				continue
 			}
 
-			logrus.Debugf("miss notification: dest IP %v, dest MAC %v", ip, mac)
-
 			if neigh.State&(netlink.NUD_STALE|netlink.NUD_INCOMPLETE) == 0 {
 				continue
 			}
 
 			if n.driver.isSerfAlive() {
+				logrus.Debugf("miss notification: dest IP %v, dest MAC %v", ip, mac)
 				mac, IPmask, vtep, err := n.driver.resolvePeer(n.id, ip)
 				if err != nil {
 					logrus.Errorf("could not resolve peer %q: %v", ip, err)
 					continue
 				}
 				n.driver.peerAdd(n.id, "dummy", ip, IPmask, mac, vtep, l2Miss, l3Miss, false)
-			} else {
-				// If the gc_thresh values are lower kernel might knock off the neighor entries.
-				// When we get a L3 miss check if its a valid peer and reprogram the neighbor
-				// entry again. Rate limit it to once attempt every 500ms, just in case a faulty
-				// container sends a flood of packets to invalid peers
-				if !l3Miss {
-					continue
-				}
-				if time.Since(t) > 500*time.Millisecond {
+			} else if l3Miss && time.Since(t) > time.Second {
+				// All the local peers will trigger a miss notification but this one is expected and the local container will reply
+				// autonomously to the ARP request
+				// In case the gc_thresh3 values is low kernel might reject new entries during peerAdd. This will trigger the following
+				// extra logs that will inform of the possible issue.
+				// Entries created would not be deleted see documentation http://man7.org/linux/man-pages/man7/arp.7.html:
+				// Entries which are marked as permanent are never deleted by the garbage-collector.
+				// The time limit here is to guarantee that the dbSearch is not
+				// done too frequently causing a stall of the peerDB operations.
+				pKey, pEntry, err := n.driver.peerDbSearch(n.id, ip)
+				if err == nil && !pEntry.isLocal {
 					t = time.Now()
-					n.programNeighbor(ip)
+					logrus.Warnf("miss notification for peer:%+v l3Miss:%t l2Miss:%t, if the problem persist check the gc_thresh on the host pKey:%+v pEntry:%+v err:%v",
+						neigh, l3Miss, l2Miss, *pKey, *pEntry, err)
 				}
 			}
 		}
 	}
 }
 
-func (n *network) programNeighbor(ip net.IP) {
-	peerMac, _, _, err := n.driver.peerDbSearch(n.id, ip)
-	if err != nil {
-		logrus.Errorf("Reprogramming on L3 miss failed for %s, no peer entry", ip)
-		return
-	}
-	s := n.getSubnetforIPAddr(ip)
-	if s == nil {
-		logrus.Errorf("Reprogramming on L3 miss failed for %s, not a valid subnet", ip)
-		return
-	}
-	sbox := n.sandbox()
-	if sbox == nil {
-		logrus.Errorf("Reprogramming on L3 miss failed for %s, overlay sandbox missing", ip)
-		return
-	}
-	if err := sbox.AddNeighbor(ip, peerMac, true, sbox.NeighborOptions().LinkName(s.vxlanName)); err != nil {
-		logrus.Errorf("Reprogramming on L3 miss failed for %s: %v", ip, err)
-		return
-	}
-}
-
 func (d *driver) addNetwork(n *network) {
 	d.Lock()
 	d.networks[n.id] = n
@@ -1090,15 +1067,6 @@ func (n *network) contains(ip net.IP) bool {
 	return false
 }
 
-func (n *network) getSubnetforIPAddr(ip net.IP) *subnet {
-	for _, s := range n.subnets {
-		if s.subnetIP.Contains(ip) {
-			return s
-		}
-	}
-	return nil
-}
-
 // getSubnetforIP returns the subnet to which the given IP belongs
 func (n *network) getSubnetforIP(ip *net.IPNet) *subnet {
 	for _, s := range n.subnets {

drivers/overlay/ov_serf.go

@@ -122,7 +122,7 @@ func (d *driver) processEvent(u serf.UserEvent) {
 	case "join":
 		d.peerAdd(nid, eid, net.ParseIP(ipStr), net.IPMask(net.ParseIP(maskStr).To4()), mac, net.ParseIP(vtepStr), false, false, false)
 	case "leave":
-		d.peerDelete(nid, eid, net.ParseIP(ipStr), net.IPMask(net.ParseIP(maskStr).To4()), mac, net.ParseIP(vtepStr))
+		d.peerDelete(nid, eid, net.ParseIP(ipStr), net.IPMask(net.ParseIP(maskStr).To4()), mac, net.ParseIP(vtepStr), false)
 	}
 }
 
@@ -135,13 +135,13 @@ func (d *driver) processQuery(q *serf.Query) {
 		fmt.Printf("Failed to scan query payload string: %v\n", err)
 	}
 
-	peerMac, peerIPMask, vtep, err := d.peerDbSearch(nid, net.ParseIP(ipStr))
+	pKey, pEntry, err := d.peerDbSearch(nid, net.ParseIP(ipStr))
 	if err != nil {
 		return
 	}
 
-	logrus.Debugf("Sending peer query resp mac %s, mask %s, vtep %s", peerMac, net.IP(peerIPMask), vtep)
-	q.Respond([]byte(fmt.Sprintf("%s %s %s", peerMac.String(), net.IP(peerIPMask).String(), vtep.String())))
+	logrus.Debugf("Sending peer query resp mac %v, mask %s, vtep %s", pKey.peerMac, net.IP(pEntry.peerIPMask).String(), pEntry.vtep)
+	q.Respond([]byte(fmt.Sprintf("%s %s %s", pKey.peerMac.String(), net.IP(pEntry.peerIPMask).String(), pEntry.vtep.String())))
 }
 
 func (d *driver) resolvePeer(nid string, peerIP net.IP) (net.HardwareAddr, net.IPMask, net.IP, error) {

drivers/overlay/overlay.go

@@ -262,7 +262,7 @@ func (d *driver) nodeJoin(advertiseAddress, bindAddress string, self bool) {
 		d.Unlock()
 
 		// If containers are already running on this network update the
-		// advertiseaddress in the peerDB
+		// advertise address in the peerDB
 		d.localJoinOnce.Do(func() {
 			d.peerDBUpdateSelf()
 		})

drivers/overlay/overlay.proto

@@ -24,4 +24,4 @@ message PeerRecord {
 	// which this container is running and can be reached by
 	// building a tunnel to that host IP.
 	string tunnel_endpoint_ip = 3 [(gogoproto.customname) = "TunnelEndpointIP"];
-}
+}