@@ -91,11 +91,6 @@ const (

 	ifaceCreatedByUser

 )

-// endpointConfiguration represents the user specified configuration for the sandbox endpoint

-type endpointConfiguration struct {

-	MacAddress net.HardwareAddr

-}

-

 // containerConfiguration represents the user specified configuration for a container

 type containerConfiguration struct {

 	ParentEndpoints []string

@@ -115,7 +110,6 @@ type bridgeEndpoint struct {

 	addr            *net.IPNet

 	addrv6          *net.IPNet

 	macAddress      net.HardwareAddr

-	config          *endpointConfiguration // User specified parameters

 	containerConfig *containerConfiguration

 	extConnConfig   *connectivityConfiguration

 	portMapping     []types.PortBinding // Operation port bindings

@@ -926,7 +920,7 @@ func setHairpinMode(nlh *netlink.Handle, link netlink.Link, enable bool) error {

 	return nil

 }

-func (d *driver) CreateEndpoint(nid, eid string, ifInfo driverapi.InterfaceInfo, epOptions map[string]interface{}) error {

+func (d *driver) CreateEndpoint(nid, eid string, ifInfo driverapi.InterfaceInfo, _ map[string]interface{}) error {

 	if ifInfo == nil {

 		return errors.New("invalid interface info passed")

 	}

@@ -963,15 +957,9 @@ func (d *driver) CreateEndpoint(nid, eid string, ifInfo driverapi.InterfaceInfo,

 		return driverapi.ErrEndpointExists(eid)

 	}

-	// Try to convert the options to endpoint configuration

-	epConfig, err := parseEndpointOptions(epOptions)

-	if err != nil {

-		return err

-	}

-

 	// Create and add the endpoint

 	n.Lock()

-	endpoint := &bridgeEndpoint{id: eid, nid: nid, config: epConfig}

+	endpoint := &bridgeEndpoint{id: eid, nid: nid}

 	n.endpoints[eid] = endpoint

 	n.Unlock()

@@ -1065,10 +1053,12 @@ func (d *driver) CreateEndpoint(nid, eid string, ifInfo driverapi.InterfaceInfo,

 	endpoint.addr = ifInfo.Address()

 	endpoint.addrv6 = ifInfo.AddressIPv6()

-	// Set the sbox's MAC if not provided. If specified, use the one configured by user, otherwise generate one based on IP.

+	// We assign a default MAC address derived from the IP address to make sure

+	// that if a container is disconnected and reconnected in a short timeframe,

+	// stale ARP entries will still point to the right container.

 	if endpoint.macAddress == nil {

-		endpoint.macAddress = electMacAddress(epConfig, endpoint.addr.IP)

-		if err = ifInfo.SetMacAddress(endpoint.macAddress); err != nil {

+		endpoint.macAddress = netutils.GenerateMACFromIP(endpoint.addr.IP)

+		if err := ifInfo.SetMacAddress(endpoint.macAddress); err != nil {

 			return err

 		}

 	}

@@ -1463,24 +1453,6 @@ func (d *driver) IsBuiltIn() bool {

 	return true

 }

-func parseEndpointOptions(epOptions map[string]interface{}) (*endpointConfiguration, error) {

-	if epOptions == nil {

-		return nil, nil

-	}

-

-	ec := &endpointConfiguration{}

-

-	if opt, ok := epOptions[netlabel.MacAddress]; ok {

-		if mac, ok := opt.(net.HardwareAddr); ok {

-			ec.MacAddress = mac

-		} else {

-			return nil, &ErrInvalidEndpointConfig{}

-		}

-	}

-

-	return ec, nil

-}

-

 func parseContainerOptions(cOptions map[string]interface{}) (*containerConfiguration, error) {

 	if cOptions == nil {

 		return nil, nil

@@ -1528,10 +1500,3 @@ func parseConnectivityOptions(cOptions map[string]interface{}) (*connectivityCon

 	return cc, nil

 }

-

-func electMacAddress(epConfig *endpointConfiguration, ip net.IP) net.HardwareAddr {

-	if epConfig != nil && epConfig.MacAddress != nil {

-		return epConfig.MacAddress

-	}

-	return netutils.GenerateMACFromIP(ip)

-}

@@ -35,7 +35,6 @@ func TestEndpointMarshalling(t *testing.T) {

 		addrv6:     ip2,

 		macAddress: mac,

 		srcName:    "veth123456",

-		config:     &endpointConfiguration{MacAddress: mac},

 		containerConfig: &containerConfiguration{

 			ParentEndpoints: []string{"one", "due", "three"},

 			ChildEndpoints:  []string{"four", "five", "six"},

@@ -90,7 +89,6 @@ func TestEndpointMarshalling(t *testing.T) {

 	if e.id != ee.id || e.nid != ee.nid || e.srcName != ee.srcName || !bytes.Equal(e.macAddress, ee.macAddress) ||

 		!types.CompareIPNet(e.addr, ee.addr) || !types.CompareIPNet(e.addrv6, ee.addrv6) ||

-		!compareEpConfig(e.config, ee.config) ||

 		!compareContainerConfig(e.containerConfig, ee.containerConfig) ||

 		!compareConnConfig(e.extConnConfig, ee.extConnConfig) ||

 		!compareBindings(e.portMapping, ee.portMapping) {

@@ -98,16 +96,6 @@ func TestEndpointMarshalling(t *testing.T) {

 	}

 }

-func compareEpConfig(a, b *endpointConfiguration) bool {

-	if a == b {

-		return true

-	}

-	if a == nil || b == nil {

-		return false

-	}

-	return bytes.Equal(a.MacAddress, b.MacAddress)

-}

-

 func compareContainerConfig(a, b *containerConfiguration) bool {

 	if a == b {

 		return true

@@ -385,10 +373,9 @@ func TestCreateFullOptionsLabels(t *testing.T) {

 	// In short here we are testing --fixed-cidr-v6 daemon option

 	// plus --mac-address run option

-	mac, _ := net.ParseMAC("aa:bb:cc:dd:ee:ff")

-	epOptions := map[string]interface{}{netlabel.MacAddress: mac}

 	te := newTestEndpoint(ipdList[0].Pool, 20)

-	err = d.CreateEndpoint("dummy", "ep1", te.Interface(), epOptions)

+	te.iface.mac = netutils.MustParseMAC("aa:bb:cc:dd:ee:ff")

+	err = d.CreateEndpoint("dummy", "ep1", te.Interface(), map[string]interface{}{})

 	if err != nil {

 		t.Fatal(err)

 	}

@@ -264,7 +264,6 @@ func (ep *bridgeEndpoint) MarshalJSON() ([]byte, error) {

 	if ep.addrv6 != nil {

 		epMap["Addrv6"] = ep.addrv6.String()

 	}

-	epMap["Config"] = ep.config

 	epMap["ContainerConfig"] = ep.containerConfig

 	epMap["ExternalConnConfig"] = ep.extConnConfig

 	epMap["PortMapping"] = ep.portMapping

@@ -300,11 +299,7 @@ func (ep *bridgeEndpoint) UnmarshalJSON(b []byte) error {

 	ep.id = epMap["id"].(string)

 	ep.nid = epMap["nid"].(string)

 	ep.srcName = epMap["SrcName"].(string)

-	d, _ := json.Marshal(epMap["Config"])

-	if err := json.Unmarshal(d, &ep.config); err != nil {

-		log.G(context.TODO()).Warnf("Failed to decode endpoint config %v", err)

-	}

-	d, _ = json.Marshal(epMap["ContainerConfig"])

+	d, _ := json.Marshal(epMap["ContainerConfig"])

 	if err := json.Unmarshal(d, &ep.containerConfig); err != nil {

 		log.G(context.TODO()).Warnf("Failed to decode endpoint container config %v", err)

 	}

@@ -149,3 +149,12 @@ func IsV6Listenable() bool {

 	})

 	return v6ListenableCached

 }

+

+// MustParseMAC returns a net.HardwareAddr or panic.

+func MustParseMAC(s string) net.HardwareAddr {

+	mac, err := net.ParseMAC(s)

+	if err != nil {

+		panic(err)

+	}

+	return mac

+}