@@ -150,6 +150,21 @@ func InitDriver(job *engine.Job) engine.Status {

 			}

 		}

+		// a bridge might exist but not have any IPv6 addr associated with it yet

+		// (for example, an existing Docker installation that has only been used

+		// with IPv4 and docker0 already is set up) In that case, we can perform

+		// the bridge init for IPv6 here, else we will error out below if --ipv6=true

+		if len(addrsv6) == 0 && enableIPv6 {

+			if err := setupIPv6Bridge(bridgeIPv6); err != nil {

+				return job.Error(err)

+			}

+			// recheck addresses now that IPv6 is setup on the bridge

+			addrv4, addrsv6, err = networkdriver.GetIfaceAddr(bridgeIface)

+			if err != nil {

+				return job.Error(err)

+			}

+		}

+

 		// TODO: Check if route to fixedCIDRv6 is set

 	}

@@ -401,21 +416,9 @@ func configureBridge(bridgeIP string, bridgeIPv6 string, enableIPv6 bool) error

 	}

 	if enableIPv6 {

-		// Enable IPv6 on the bridge

-		procFile := "/proc/sys/net/ipv6/conf/" + iface.Name + "/disable_ipv6"

-		if err := ioutil.WriteFile(procFile, []byte{'0', '\n'}, 0644); err != nil {

-			return fmt.Errorf("unable to enable IPv6 addresses on bridge: %s\n", err)

-		}

-

-		ipAddr6, ipNet6, err := net.ParseCIDR(bridgeIPv6)

-		if err != nil {

-			log.Errorf("BridgeIPv6 parsing failed")

+		if err := setupIPv6Bridge(bridgeIPv6); err != nil {

 			return err

 		}

-

-		if err := netlink.NetworkLinkAddIp(iface, ipAddr6, ipNet6); err != nil {

-			return fmt.Errorf("Unable to add private IPv6 network: %s", err)

-		}

 	}

 	if err := netlink.NetworkLinkUp(iface); err != nil {

@@ -424,6 +427,30 @@ func configureBridge(bridgeIP string, bridgeIPv6 string, enableIPv6 bool) error

 	return nil

 }

+func setupIPv6Bridge(bridgeIPv6 string) error {

+

+	iface, err := net.InterfaceByName(bridgeIface)

+	if err != nil {

+		return err

+	}

+	// Enable IPv6 on the bridge

+	procFile := "/proc/sys/net/ipv6/conf/" + iface.Name + "/disable_ipv6"

+	if err := ioutil.WriteFile(procFile, []byte{'0', '\n'}, 0644); err != nil {

+		return fmt.Errorf("Unable to enable IPv6 addresses on bridge: %v", err)

+	}

+

+	ipAddr6, ipNet6, err := net.ParseCIDR(bridgeIPv6)

+	if err != nil {

+		return fmt.Errorf("Unable to parse bridge IPv6 address: %q, error: %v", bridgeIPv6, err)

+	}

+

+	if err := netlink.NetworkLinkAddIp(iface, ipAddr6, ipNet6); err != nil {

+		return fmt.Errorf("Unable to add private IPv6 network: %v", err)

+	}

+

+	return nil

+}

+

 func createBridgeIface(name string) error {

 	kv, err := kernel.GetKernelVersion()

 	// only set the bridge's mac address if the kernel version is > 3.3

@@ -74,7 +74,7 @@ func NetworkRange(network *net.IPNet) (net.IP, net.IP) {

 	return netIP.Mask(network.Mask), net.IP(lastIP)

 }

-// Return the IPv4 address of a network interface

+// Return the first IPv4 address and slice of IPv6 addresses for the specified network interface

 func GetIfaceAddr(name string) (net.Addr, []net.Addr, error) {

 	iface, err := net.InterfaceByName(name)

 	if err != nil {