diff --git a/backend/alivpc/alivpc.go b/backend/alivpc/alivpc.go
index 1b6b1cedd..14041e8d1 100644
--- a/backend/alivpc/alivpc.go
+++ b/backend/alivpc/alivpc.go
@@ -18,7 +18,6 @@ package alivpc
 import (
 	"encoding/json"
 	"fmt"
-	"golang.org/x/net/context"
 	"os"
 	"sync"
 
@@ -28,6 +27,7 @@ import (
 	"github.com/flannel-io/flannel/backend"
 	"github.com/flannel-io/flannel/pkg/ip"
 	"github.com/flannel-io/flannel/subnet"
+	"golang.org/x/net/context"
 	log "k8s.io/klog"
 )
 
diff --git a/backend/alivpc/alivpc_windows.go b/backend/alivpc/alivpc_windows.go
index 123f1fcd1..e2c0e1d31 100644
--- a/backend/alivpc/alivpc_windows.go
+++ b/backend/alivpc/alivpc_windows.go
@@ -13,11 +13,3 @@
 // limitations under the License.
 
 package alivpc
-
-import (
-	log "k8s.io/klog"
-)
-
-func init() {
-	log.Infof("AliVpc is not supported on this platform")
-}
diff --git a/backend/awsvpc/awsvpc.go b/backend/awsvpc/awsvpc.go
index 1629629ad..5f4c5110d 100644
--- a/backend/awsvpc/awsvpc.go
+++ b/backend/awsvpc/awsvpc.go
@@ -26,11 +26,10 @@ import (
 	"github.com/aws/aws-sdk-go/aws/ec2metadata"
 	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/aws/aws-sdk-go/service/ec2"
-	"golang.org/x/net/context"
-
 	"github.com/flannel-io/flannel/backend"
 	"github.com/flannel-io/flannel/pkg/ip"
 	"github.com/flannel-io/flannel/subnet"
+	"golang.org/x/net/context"
 	log "k8s.io/klog"
 )
 
diff --git a/backend/awsvpc/awsvpc_windows.go b/backend/awsvpc/awsvpc_windows.go
index cca820751..48c77d137 100644
--- a/backend/awsvpc/awsvpc_windows.go
+++ b/backend/awsvpc/awsvpc_windows.go
@@ -13,11 +13,3 @@
 // limitations under the License.
 
 package awsvpc
-
-import (
-	log "k8s.io/klog"
-)
-
-func init() {
-	log.Infof("AWS VPC is not supported on this platform")
-}
diff --git a/backend/common.go b/backend/common.go
index 4ee9c6f4f..3505d442f 100644
--- a/backend/common.go
+++ b/backend/common.go
@@ -18,9 +18,8 @@ import (
 	"net"
 	"sync"
 
-	"golang.org/x/net/context"
-
 	"github.com/flannel-io/flannel/subnet"
+	"golang.org/x/net/context"
 )
 
 type ExternalInterface struct {
diff --git a/backend/gce/gce_windows.go b/backend/gce/gce_windows.go
index dd40c87b0..c0ad20238 100644
--- a/backend/gce/gce_windows.go
+++ b/backend/gce/gce_windows.go
@@ -36,11 +36,3 @@
 // SOFTWARE.
 
 package gce
-
-import (
-	log "k8s.io/klog"
-)
-
-func init() {
-	log.Infof("GCE is not supported on this platform")
-}
diff --git a/backend/hostgw/hostgw.go b/backend/hostgw/hostgw.go
index f36702009..d10639d45 100644
--- a/backend/hostgw/hostgw.go
+++ b/backend/hostgw/hostgw.go
@@ -19,7 +19,6 @@ package hostgw
 
 import (
 	"fmt"
-
 	"sync"
 
 	"github.com/flannel-io/flannel/backend"
diff --git a/backend/ipip/ipip_windows.go b/backend/ipip/ipip_windows.go
index 41893b5a0..401d391cf 100644
--- a/backend/ipip/ipip_windows.go
+++ b/backend/ipip/ipip_windows.go
@@ -14,11 +14,3 @@
 // +build windows
 
 package ipip
-
-import (
-	log "k8s.io/klog"
-)
-
-func init() {
-	log.Infof("ipip is not supported on this platform")
-}
diff --git a/backend/ipsec/ipsec_windows.go b/backend/ipsec/ipsec_windows.go
index 0a0ef94b6..ec96b64c9 100644
--- a/backend/ipsec/ipsec_windows.go
+++ b/backend/ipsec/ipsec_windows.go
@@ -13,9 +13,3 @@
 // limitations under the License.
 
 package ipsec
-
-import log "k8s.io/klog"
-
-func init() {
-	log.Infof("ipsec is not supported on this platform")
-}
diff --git a/backend/manager.go b/backend/manager.go
index 4455466cc..98a170aba 100644
--- a/backend/manager.go
+++ b/backend/manager.go
@@ -19,9 +19,8 @@ import (
 	"strings"
 	"sync"
 
-	"golang.org/x/net/context"
-
 	"github.com/flannel-io/flannel/subnet"
+	"golang.org/x/net/context"
 )
 
 var constructors = make(map[string]BackendCtor)
diff --git a/backend/route_network.go b/backend/route_network.go
index cabd47f71..fb60398e2 100644
--- a/backend/route_network.go
+++ b/backend/route_network.go
@@ -22,10 +22,9 @@ import (
 	"sync"
 	"time"
 
-	"golang.org/x/net/context"
-
 	"github.com/flannel-io/flannel/subnet"
 	"github.com/vishvananda/netlink"
+	"golang.org/x/net/context"
 	log "k8s.io/klog"
 )
 
diff --git a/backend/route_network_windows.go b/backend/route_network_windows.go
index de5031269..eebf09e1e 100644
--- a/backend/route_network_windows.go
+++ b/backend/route_network_windows.go
@@ -19,10 +19,9 @@ import (
 	"sync"
 	"time"
 
-	"golang.org/x/net/context"
-
 	"github.com/flannel-io/flannel/pkg/routing"
 	"github.com/flannel-io/flannel/subnet"
+	"golang.org/x/net/context"
 	log "k8s.io/klog"
 )
 
diff --git a/backend/simple_network.go b/backend/simple_network.go
index d48e02a85..652a99a18 100644
--- a/backend/simple_network.go
+++ b/backend/simple_network.go
@@ -15,9 +15,8 @@
 package backend
 
 import (
-	"golang.org/x/net/context"
-
 	"github.com/flannel-io/flannel/subnet"
+	"golang.org/x/net/context"
 )
 
 type SimpleNetwork struct {
diff --git a/backend/tencentvpc/tencentvpc_windows.go b/backend/tencentvpc/tencentvpc_windows.go
index 2aacaa1fa..985a6570f 100644
--- a/backend/tencentvpc/tencentvpc_windows.go
+++ b/backend/tencentvpc/tencentvpc_windows.go
@@ -13,11 +13,3 @@
 // limitations under the License.
 
 package tencentvpc
-
-import (
-	log "k8s.io/klog"
-)
-
-func init() {
-	log.Infof("TencentVpc is not supported on this platform")
-}
diff --git a/backend/udp/udp_amd64.go b/backend/udp/udp_amd64.go
index d375bc1af..26e43becc 100644
--- a/backend/udp/udp_amd64.go
+++ b/backend/udp/udp_amd64.go
@@ -20,11 +20,10 @@ import (
 	"fmt"
 	"sync"
 
-	"golang.org/x/net/context"
-
 	"github.com/flannel-io/flannel/backend"
 	"github.com/flannel-io/flannel/pkg/ip"
 	"github.com/flannel-io/flannel/subnet"
+	"golang.org/x/net/context"
 )
 
 func init() {
diff --git a/backend/udp/udp_network_amd64.go b/backend/udp/udp_network_amd64.go
index 7f9d3f778..528f74b18 100644
--- a/backend/udp/udp_network_amd64.go
+++ b/backend/udp/udp_network_amd64.go
@@ -24,12 +24,11 @@ import (
 	"sync"
 	"syscall"
 
-	"golang.org/x/net/context"
-
 	"github.com/flannel-io/flannel/backend"
 	"github.com/flannel-io/flannel/pkg/ip"
 	"github.com/flannel-io/flannel/subnet"
 	"github.com/vishvananda/netlink"
+	"golang.org/x/net/context"
 	log "k8s.io/klog"
 )
 
diff --git a/backend/udp/udp_windows.go b/backend/udp/udp_windows.go
index 3e2154b5e..2209dba99 100644
--- a/backend/udp/udp_windows.go
+++ b/backend/udp/udp_windows.go
@@ -13,11 +13,3 @@
 // limitations under the License.
 
 package udp
-
-import (
-	log "k8s.io/klog"
-)
-
-func init() {
-	log.Infof("udp is not supported on this platform")
-}
diff --git a/backend/vxlan/vxlan.go b/backend/vxlan/vxlan.go
index 871aa6bd1..c5bc11160 100644
--- a/backend/vxlan/vxlan.go
+++ b/backend/vxlan/vxlan.go
@@ -58,11 +58,10 @@ import (
 	"net"
 	"sync"
 
-	"golang.org/x/net/context"
-
 	"github.com/flannel-io/flannel/backend"
 	"github.com/flannel-io/flannel/pkg/ip"
 	"github.com/flannel-io/flannel/subnet"
+	"golang.org/x/net/context"
 	log "k8s.io/klog"
 )
 
diff --git a/backend/vxlan/vxlan_network.go b/backend/vxlan/vxlan_network.go
index 17c09354a..089831a29 100644
--- a/backend/vxlan/vxlan_network.go
+++ b/backend/vxlan/vxlan_network.go
@@ -21,12 +21,11 @@ import (
 	"sync"
 	"syscall"
 
-	"golang.org/x/net/context"
-
 	"github.com/flannel-io/flannel/backend"
 	"github.com/flannel-io/flannel/pkg/ip"
 	"github.com/flannel-io/flannel/subnet"
 	"github.com/vishvananda/netlink"
+	"golang.org/x/net/context"
 	log "k8s.io/klog"
 )
 
diff --git a/backend/vxlan/vxlan_network_windows.go b/backend/vxlan/vxlan_network_windows.go
index 2d8391dbc..4a5d402c6 100644
--- a/backend/vxlan/vxlan_network_windows.go
+++ b/backend/vxlan/vxlan_network_windows.go
@@ -20,12 +20,11 @@ import (
 	"strings"
 	"sync"
 
-	"golang.org/x/net/context"
-
 	"github.com/Microsoft/hcsshim/hcn"
 	"github.com/flannel-io/flannel/backend"
 	"github.com/flannel-io/flannel/pkg/ip"
 	"github.com/flannel-io/flannel/subnet"
+	"golang.org/x/net/context"
 	log "k8s.io/klog"
 )
 
diff --git a/backend/vxlan/vxlan_windows.go b/backend/vxlan/vxlan_windows.go
index 1943b226e..e6b94bd5a 100644
--- a/backend/vxlan/vxlan_windows.go
+++ b/backend/vxlan/vxlan_windows.go
@@ -30,12 +30,11 @@ import (
 	"net"
 	"sync"
 
-	"golang.org/x/net/context"
-
 	"github.com/Microsoft/hcsshim/hcn"
 	"github.com/flannel-io/flannel/backend"
 	"github.com/flannel-io/flannel/pkg/ip"
 	"github.com/flannel-io/flannel/subnet"
+	"golang.org/x/net/context"
 	log "k8s.io/klog"
 )
 
diff --git a/main.go b/main.go
index d2e524a69..374171514 100644
--- a/main.go
+++ b/main.go
@@ -311,8 +311,6 @@ func main() {
 		}
 	}
 
-
-
 	// Create a backend manager then use it to create the backend and register the network with it.
 	bm := backend.NewManager(ctx, sm, extIface)
 	be, err := bm.GetBackend(config.BackendType)
@@ -521,10 +519,13 @@ func LookupExtIface(ifname string, ifregexS string, ipStack int) (*backend.Exter
 	var ifaceAddr net.IP
 	var ifaceV6Addr net.IP
 	var err error
+	var ifregex *regexp.Regexp
 
-        ifregex, err := regexp.Compile(ifregexS)
-	if err != nil {
-		return nil, fmt.Errorf("could not compile the IP address regex '%s': %w", ifregexS, err)
+	if ifregexS != "" {
+		ifregex, err = regexp.Compile(ifregexS)
+		if err != nil {
+			return nil, fmt.Errorf("could not compile the IP address regex '%s': %w", ifregexS, err)
+		}
 	}
 
 	// Check ip family stack
@@ -565,7 +566,7 @@ func LookupExtIface(ifname string, ifregexS string, ipStack int) (*backend.Exter
 				return nil, fmt.Errorf("error looking up interface %s: %s", ifname, err)
 			}
 		}
-	} else if len(ifregex) > 0 {
+	} else if ifregex != nil {
 		// Use the regex if specified and the iface option for matching a specific ip or name is not used
 		ifaces, err := net.Interfaces()
 		if err != nil {
@@ -582,12 +583,7 @@ func LookupExtIface(ifname string, ifregexS string, ipStack int) (*backend.Exter
 					continue
 				}
 
-				matched, err := ifregex.MatchString(ifaceIP.String())
-				if err != nil {
-					return nil, fmt.Errorf("regex error matching pattern %s to %s", ifregexS, ifaceIP.String())
-				}
-
-				if matched {
+				if ifregex.MatchString(ifaceIP.String()) {
 					ifaceAddr = ifaceIP
 					iface = &ifaceToMatch
 					break
@@ -599,12 +595,7 @@ func LookupExtIface(ifname string, ifregexS string, ipStack int) (*backend.Exter
 					continue
 				}
 
-				matched, err := ifregex.MatchString(ifaceIP.String())
-				if err != nil {
-					return nil, fmt.Errorf("regex error matching pattern %s to %s", ifregexS, ifaceIP.String())
-				}
-
-				if matched {
+				if ifregex.MatchString(ifaceIP.String()) {
 					ifaceV6Addr = ifaceIP
 					iface = &ifaceToMatch
 					break
@@ -616,23 +607,13 @@ func LookupExtIface(ifname string, ifregexS string, ipStack int) (*backend.Exter
 					continue
 				}
 
-				matched, err := ifregex.MatchString(ifaceIP.String())
-				if err != nil {
-					return nil, fmt.Errorf("regex error matching pattern %s to %s", ifregexS, ifaceIP.String())
-				}
-
 				ifaceV6IP, err := ip.GetInterfaceIP6Addr(&ifaceToMatch)
 				if err != nil {
 					// Skip if there is no IPv6 address
 					continue
 				}
 
-				v6Matched, err := ifregex.MatchString(ifaceV6IP.String())
-				if err != nil {
-					return nil, fmt.Errorf("regex error matching pattern %s to %s", ifregexS, ifaceIP.String())
-				}
-
-				if matched && v6Matched {
+				if ifregex.MatchString(ifaceIP.String()) && ifregex.MatchString(ifaceV6IP.String()) {
 					ifaceAddr = ifaceIP
 					ifaceV6Addr = ifaceV6IP
 					iface = &ifaceToMatch
@@ -644,12 +625,7 @@ func LookupExtIface(ifname string, ifregexS string, ipStack int) (*backend.Exter
 		// Check Name
 		if iface == nil && (ifaceAddr == nil || ifaceV6Addr == nil) {
 			for _, ifaceToMatch := range ifaces {
-				matched, err := ifregex.MatchString(ifaceToMatch.Name)
-				if err != nil {
-					return nil, fmt.Errorf("regex error matching pattern %s to %s", ifregexS, ifaceToMatch.Name)
-				}
-
-				if matched {
+				if ifregex.MatchString(ifaceToMatch.Name) {
 					iface = &ifaceToMatch
 					break
 				}
diff --git a/network/iptables_windows.go b/network/iptables_windows.go
index fe563f8e6..541665cd8 100644
--- a/network/iptables_windows.go
+++ b/network/iptables_windows.go
@@ -31,21 +31,11 @@ type IPTablesRule struct {
 	rulespec []string
 }
 
-func MasqRules(ipn ip.IP4Net, lease *subnet.Lease) []IPTablesRule {
-	return nil
-}
-
-func ForwardRules(flannelNetwork string) []IPTablesRule {
-	return nil
-}
-
-func SetupAndEnsureIPTables(rules []IPTablesRule, resyncPeriod int) {
-
-}
-
-func DeleteIPTables(rules []IPTablesRule) error {
-	return nil
-}
-
-func teardownIPTables(ipt IPTables, rules []IPTablesRule) {
-}
+func MasqRules(ipn ip.IP4Net, lease *subnet.Lease) []IPTablesRule    { return nil }
+func ForwardRules(flannelNetwork string) []IPTablesRule              { return nil }
+func SetupAndEnsureIPTables(rules []IPTablesRule, resyncPeriod int)  {}
+func DeleteIPTables(rules []IPTablesRule) error                      { return nil }
+func teardownIPTables(ipt IPTables, rules []IPTablesRule)            {}
+func SetupAndEnsureIP6Tables(rules []IPTablesRule, resyncPeriod int) {}
+func MasqIP6Rules(ipn ip.IP6Net, lease *subnet.Lease) []IPTablesRule { return nil }
+func DeleteIP6Tables(rules []IPTablesRule) error                     { return nil }
diff --git a/pkg/ip/iface_windows.go b/pkg/ip/iface_windows.go
index e2b498e45..a9f4e6cf8 100644
--- a/pkg/ip/iface_windows.go
+++ b/pkg/ip/iface_windows.go
@@ -19,8 +19,9 @@ package ip
 import (
 	"errors"
 	"fmt"
-	"github.com/flannel-io/flannel/pkg/powershell"
 	"net"
+
+	"github.com/flannel-io/flannel/pkg/powershell"
 )
 
 // GetInterfaceIP4Addr returns the IPv4 address for the given network interface
@@ -143,3 +144,7 @@ func IsForwardingEnabledForInterface(iface *net.Interface) (bool, error) {
 
 	return powerShellJsonData.Forwarding == 1, nil
 }
+
+func GetInterfaceByIP6(ip net.IP) (*net.Interface, error)      { return nil, nil }
+func GetInterfaceIP6Addr(iface *net.Interface) (net.IP, error) { return nil, nil }
+func GetDefaultV6GatewayInterface() (*net.Interface, error)    { return nil, nil }
diff --git a/subnet/etcdv2/mock_registry.go b/subnet/etcdv2/mock_registry.go
index f33b8e664..fc3ab7a0c 100644
--- a/subnet/etcdv2/mock_registry.go
+++ b/subnet/etcdv2/mock_registry.go
@@ -20,11 +20,10 @@ import (
 	"time"
 
 	etcd "github.com/coreos/etcd/client"
-	"github.com/jonboulle/clockwork"
-	"golang.org/x/net/context"
-
 	"github.com/flannel-io/flannel/pkg/ip"
 	. "github.com/flannel-io/flannel/subnet"
+	"github.com/jonboulle/clockwork"
+	"golang.org/x/net/context"
 )
 
 var clock clockwork.Clock = clockwork.NewRealClock()
diff --git a/subnet/etcdv2/registry_test.go b/subnet/etcdv2/registry_test.go
index 81bb551df..ed98b3d17 100644
--- a/subnet/etcdv2/registry_test.go
+++ b/subnet/etcdv2/registry_test.go
@@ -21,10 +21,9 @@ import (
 	"time"
 
 	etcd "github.com/coreos/etcd/client"
-	"golang.org/x/net/context"
-
 	"github.com/flannel-io/flannel/pkg/ip"
 	. "github.com/flannel-io/flannel/subnet"
+	"golang.org/x/net/context"
 )
 
 func newTestEtcdRegistry(t *testing.T) (Registry, *mockEtcd) {
diff --git a/subnet/watch.go b/subnet/watch.go
index 84cea8b0a..8915fd9b1 100644
--- a/subnet/watch.go
+++ b/subnet/watch.go
@@ -17,9 +17,8 @@ package subnet
 import (
 	"time"
 
-	"golang.org/x/net/context"
-
 	"github.com/flannel-io/flannel/pkg/ip"
+	"golang.org/x/net/context"
 	log "k8s.io/klog"
 )
 
diff --git a/version/version.go b/version/version.go
index 2521a30ee..070cfb5b4 100644
--- a/version/version.go
+++ b/version/version.go
@@ -14,4 +14,4 @@
 
 package version
 
-var Version = "0.5.3+git"
+var Version = "dev"