added logic to fix cns bug for overlay subnet expansion

Author: Riya

cns/NetworkContainerContract.go

@@ -129,6 +129,7 @@ type CreateNetworkContainerRequest struct {
 	EndpointPolicies           []NetworkContainerRequestPolicies
 	NCStatus                   v1alpha.NCStatus
 	NetworkInterfaceInfo       NetworkInterfaceInfo //nolint // introducing new field for backendnic, to be used later by cni code
+	Scenario                   v1alpha.NCType       //nolint // introducing new field for nnc reconciler
 }
 
 func (req *CreateNetworkContainerRequest) Validate() error {

cns/kubecontroller/nodenetworkconfig/conversion.go

@@ -67,6 +67,7 @@ func CreateNCRequestFromDynamicNC(nc v1alpha.NetworkContainer) (*cns.CreateNetwo
 			GatewayIPAddress: nc.DefaultGateway,
 		},
 		NCStatus: nc.Status,
+		Scenario: nc.Type,
 	}, nil
 }
 

cns/kubecontroller/nodenetworkconfig/conversion_linux.go

@@ -63,5 +63,6 @@ func createNCRequestFromStaticNCHelper(nc v1alpha.NetworkContainer, primaryIPPre
 		NetworkInterfaceInfo: cns.NetworkInterfaceInfo{
 			MACAddress: nc.MacAddress,
 		},
+		Scenario: nc.Type,
 	}, nil
 }

cns/restserver/internalapi.go

@@ -630,13 +630,15 @@ func (service *HTTPRestService) CreateOrUpdateNetworkContainerInternal(req *cns.
 	if ok {
 		existingReq := existingNCInfo.CreateNetworkContainerRequest
 		if !reflect.DeepEqual(existingReq.IPConfiguration.IPSubnet, req.IPConfiguration.IPSubnet) {
-			logger.Errorf("[Azure CNS] Error. PrimaryCA is not same, NCId %s, old CA %s/%d, new CA %s/%d",
-				req.NetworkContainerid,
-				existingReq.IPConfiguration.IPSubnet.IPAddress,
-				existingReq.IPConfiguration.IPSubnet.PrefixLength,
-				req.IPConfiguration.IPSubnet.IPAddress,
-				req.IPConfiguration.IPSubnet.PrefixLength)
-			return types.PrimaryCANotSame
+			if req.Scenario != v1alpha.Overlay { // if overlay -> potentially an overlay subnet expansion is occuring, skip this check
+				logger.Errorf("[Azure CNS] Error. PrimaryCA is not same, NCId %s, old CA %s/%d, new CA %s/%d",
+					req.NetworkContainerid,
+					existingReq.IPConfiguration.IPSubnet.IPAddress,
+					existingReq.IPConfiguration.IPSubnet.PrefixLength,
+					req.IPConfiguration.IPSubnet.IPAddress,
+					req.IPConfiguration.IPSubnet.PrefixLength)
+				return types.PrimaryCANotSame
+			}
 		}
 	}
 

cns/restserver/util.go

@@ -174,7 +174,6 @@ func (service *HTTPRestService) saveNetworkContainerGoalState(req cns.CreateNetw
 	// Remove the auth token before saving the containerStatus to cns json file
 	createNetworkContainerRequest := req
 	createNetworkContainerRequest.AuthorizationToken = ""
-
 	service.state.ContainerStatus[req.NetworkContainerid] = containerstatus{
 		ID:                            req.NetworkContainerid,
 		VMVersion:                     req.Version,