Allow IP addresses to be used as node names

pkg/api/validation/validation.go

@@ -3435,9 +3435,11 @@ func validateEndpointAddress(address *api.EndpointAddress, fldPath *field.Path,
 	if len(address.Hostname) > 0 {
 		allErrs = append(allErrs, ValidateDNS1123Label(address.Hostname, fldPath.Child("hostname"))...)
 	}
-	// During endpoint update, validate NodeName is DNS1123 compliant and transition rules allow the update
+	// During endpoint update, verify that NodeName is a DNS subdomain and transition rules allow the update
 	if address.NodeName != nil {
-		allErrs = append(allErrs, ValidateDNS1123Label(*address.NodeName, fldPath.Child("nodeName"))...)
+		for _, msg := range ValidateNodeName(*address.NodeName, false) {
+			allErrs = append(allErrs, field.Invalid(fldPath.Child("nodeName"), *address.NodeName, msg))
+		}
 	}
 	allErrs = append(allErrs, validateEpAddrNodeNameTransition(address, ipToNodeName, fldPath.Child("nodeName"))...)
 	if len(allErrs) > 0 {

pkg/api/validation/validation_test.go

@@ -8023,11 +8023,19 @@ func TestEndpointAddressNodeNameUpdateRestrictions(t *testing.T) {
 	}
 }
 
-func TestEndpointAddressNodeNameInvalidDNS1123(t *testing.T) {
+func TestEndpointAddressNodeNameInvalidDNSSubdomain(t *testing.T) {
 	// Check NodeName DNS validation
-	endpoint := newNodeNameEndpoint("illegal.nodename")
+	endpoint := newNodeNameEndpoint("illegal*.nodename")
 	errList := ValidateEndpoints(endpoint)
 	if len(errList) == 0 {
 		t.Error("Endpoint should reject invalid NodeName")
 	}
 }
+
+func TestEndpointAddressNodeNameCanBeAnIPAddress(t *testing.T) {
+	endpoint := newNodeNameEndpoint("10.10.1.1")
+	errList := ValidateEndpoints(endpoint)
+	if len(errList) != 0 {
+		t.Error("Endpoint should accept a NodeName that is an IP address")
+	}
+}