diff --git a/internal/hns/hnspolicy.go b/internal/hns/hnspolicy.go
index 6765aaead5..994ab81bb7 100644
--- a/internal/hns/hnspolicy.go
+++ b/internal/hns/hnspolicy.go
@@ -21,10 +21,11 @@ const (
 )
 
 type NatPolicy struct {
-	Type         PolicyType `json:"Type"`
-	Protocol     string
-	InternalPort uint16
-	ExternalPort uint16
+	Type                 PolicyType `json:"Type"`
+	Protocol             string
+	InternalPort         uint16
+	ExternalPort         uint16
+	ExternalPortReserved bool       `json:",omitempty"`
 }
 
 type QosPolicy struct {
diff --git a/test/vendor/github.com/Microsoft/hcsshim/internal/hns/hnspolicy.go b/test/vendor/github.com/Microsoft/hcsshim/internal/hns/hnspolicy.go
index 6765aaead5..b6cdcc269a 100644
--- a/test/vendor/github.com/Microsoft/hcsshim/internal/hns/hnspolicy.go
+++ b/test/vendor/github.com/Microsoft/hcsshim/internal/hns/hnspolicy.go
@@ -21,10 +21,11 @@ const (
 )
 
 type NatPolicy struct {
-	Type         PolicyType `json:"Type"`
-	Protocol     string
-	InternalPort uint16
-	ExternalPort uint16
+	Type                 PolicyType `json:"Type"`
+	Protocol             string
+	InternalPort         uint16
+	ExternalPort         uint16
+	ExternalPortReserved bool `json:",omitempty"`
 }
 
 type QosPolicy struct {