diff --git a/rw_core/mocks/adapter.go b/rw_core/mocks/adapter.go
index e14457d..3c29a01 100644
--- a/rw_core/mocks/adapter.go
+++ b/rw_core/mocks/adapter.go
@@ -17,6 +17,7 @@
 package mocks
 
 import (
+	"fmt"
 	"strconv"
 	"strings"
 	"sync"
@@ -25,8 +26,6 @@
 	ic "github.com/opencord/voltha-protos/v3/go/inter_container"
 	of "github.com/opencord/voltha-protos/v3/go/openflow_13"
 	"github.com/opencord/voltha-protos/v3/go/voltha"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/status"
 )
 
 func macAddressToUint32Array(mac string) []uint32 {
@@ -45,39 +44,40 @@
 
 // Adapter represents adapter attributes
 type Adapter struct {
-	coreProxy adapterif.CoreProxy
-	devices   sync.Map
+	coreProxy      adapterif.CoreProxy
+	flows          map[uint64]*voltha.OfpFlowStats
+	flowLock       sync.RWMutex
+	devices        map[string]*voltha.Device
+	deviceLock     sync.RWMutex
+	failFlowAdd    bool
+	failFlowDelete bool
 }
 
 // NewAdapter creates adapter instance
 func NewAdapter(cp adapterif.CoreProxy) *Adapter {
 	return &Adapter{
+		flows:     map[uint64]*voltha.OfpFlowStats{},
+		devices:   map[string]*voltha.Device{},
 		coreProxy: cp,
 	}
 }
 
 func (ta *Adapter) storeDevice(d *voltha.Device) {
+	ta.deviceLock.Lock()
+	defer ta.deviceLock.Unlock()
 	if d != nil {
-		ta.devices.Store(d.Id, d)
+		ta.devices[d.Id] = d
 	}
 }
 
 func (ta *Adapter) getDevice(id string) *voltha.Device {
-	if val, ok := ta.devices.Load(id); ok && val != nil {
-		if device, ok := val.(*voltha.Device); ok {
-			return device
-		}
-	}
-	return nil
+	ta.deviceLock.RLock()
+	defer ta.deviceLock.RUnlock()
+	return ta.devices[id]
 }
 
-func (ta *Adapter) updateDevice(d *voltha.Device) error {
-	if d != nil {
-		if _, ok := ta.devices.LoadOrStore(d.Id, d); !ok {
-			return status.Errorf(codes.Internal, "error updating device %s", d.Id)
-		}
-	}
-	return nil
+func (ta *Adapter) updateDevice(d *voltha.Device) {
+	ta.storeDevice(d)
 }
 
 // Adapter_descriptor -
@@ -145,8 +145,27 @@
 	return nil
 }
 
-// Update_flows_incrementally -
+// Update_flows_incrementally mocks the incremental flow update
 func (ta *Adapter) Update_flows_incrementally(device *voltha.Device, flows *of.FlowChanges, groups *of.FlowGroupChanges, flowMetadata *voltha.FlowMetadata) error { // nolint
+	ta.flowLock.Lock()
+	defer ta.flowLock.Unlock()
+
+	if flows.ToAdd != nil {
+		if ta.failFlowAdd {
+			return fmt.Errorf("flow-add-error")
+		}
+		for _, f := range flows.ToAdd.Items {
+			ta.flows[f.Id] = f
+		}
+	}
+	if flows.ToRemove != nil {
+		if ta.failFlowDelete {
+			return fmt.Errorf("flow-delete-error")
+		}
+		for _, f := range flows.ToRemove.Items {
+			delete(ta.flows, f.Id)
+		}
+	}
 	return nil
 }
 
@@ -263,3 +282,25 @@
 func (ta *Adapter) Get_ext_value(deviceId string, device *voltha.Device, valueflag voltha.ValueType_Type) (*voltha.ReturnValues, error) { //nolint
 	return nil, nil
 }
+
+// GetFlowCount returns the total number of flows presently under this adapter
+func (ta *Adapter) GetFlowCount() int {
+	ta.flowLock.RLock()
+	defer ta.flowLock.RUnlock()
+
+	return len(ta.flows)
+}
+
+// ClearFlows removes all flows in this adapter
+func (ta *Adapter) ClearFlows() {
+	ta.flowLock.Lock()
+	defer ta.flowLock.Unlock()
+
+	ta.flows = map[uint64]*voltha.OfpFlowStats{}
+}
+
+// SetFlowAction sets the adapter action on addition and deletion of flows
+func (ta *Adapter) SetFlowAction(failFlowAdd, failFlowDelete bool) {
+	ta.failFlowAdd = failFlowAdd
+	ta.failFlowDelete = failFlowDelete
+}
diff --git a/rw_core/mocks/adapter_olt.go b/rw_core/mocks/adapter_olt.go
index 3ccecc7..61f431a 100644
--- a/rw_core/mocks/adapter_olt.go
+++ b/rw_core/mocks/adapter_olt.go
@@ -20,9 +20,6 @@
 	"context"
 	"errors"
 	"fmt"
-	"strings"
-	"sync"
-
 	"github.com/gogo/protobuf/proto"
 	"github.com/opencord/voltha-lib-go/v3/pkg/adapters/adapterif"
 	com "github.com/opencord/voltha-lib-go/v3/pkg/adapters/common"
@@ -30,6 +27,7 @@
 	ic "github.com/opencord/voltha-protos/v3/go/inter_container"
 	of "github.com/opencord/voltha-protos/v3/go/openflow_13"
 	"github.com/opencord/voltha-protos/v3/go/voltha"
+	"strings"
 )
 
 const (
@@ -39,18 +37,13 @@
 
 // OLTAdapter represent OLT adapter
 type OLTAdapter struct {
-	flows map[uint64]*voltha.OfpFlowStats
-	lock  sync.Mutex
-	Adapter
+	*Adapter
 }
 
 // NewOLTAdapter - creates OLT adapter instance
 func NewOLTAdapter(cp adapterif.CoreProxy) *OLTAdapter {
 	return &OLTAdapter{
-		flows: map[uint64]*voltha.OfpFlowStats{},
-		Adapter: Adapter{
-			coreProxy: cp,
-		},
+		Adapter: NewAdapter(cp),
 	}
 }
 
@@ -100,9 +93,7 @@
 			logger.Fatalf("getting-device-failed-%s", err)
 		}
 
-		if err = oltA.updateDevice(d); err != nil {
-			logger.Fatalf("saving-device-failed-%s", err)
-		}
+		oltA.updateDevice(d)
 
 		// Register Child devices
 		initialUniPortNo := startingUNIPortNo
@@ -204,9 +195,7 @@
 			return
 		}
 
-		if err := oltA.updateDevice(cloned); err != nil {
-			logger.Fatalf("saving-device-failed-%s", err)
-		}
+		oltA.updateDevice(cloned)
 
 		// Tell the Core that all child devices have been disabled (by default it's an action already taken by the Core
 		if err := oltA.coreProxy.ChildDevicesLost(context.TODO(), cloned.Id); err != nil {
@@ -278,24 +267,6 @@
 	return nil
 }
 
-// Update_flows_incrementally mocks the incremental flow update
-func (oltA *OLTAdapter) Update_flows_incrementally(device *voltha.Device, flows *of.FlowChanges, groups *of.FlowGroupChanges, flowMetadata *voltha.FlowMetadata) error { // nolint
-	oltA.lock.Lock()
-	defer oltA.lock.Unlock()
-
-	if flows.ToAdd != nil {
-		for _, f := range flows.ToAdd.Items {
-			oltA.flows[f.Id] = f
-		}
-	}
-	if flows.ToRemove != nil {
-		for _, f := range flows.ToRemove.Items {
-			delete(oltA.flows, f.Id)
-		}
-	}
-	return nil
-}
-
 // Reboot_device -
 func (oltA *OLTAdapter) Reboot_device(device *voltha.Device) error { // nolint
 	logger.Infow("reboot-device", log.Fields{"deviceId": device.Id})
@@ -305,7 +276,8 @@
 			logger.Fatalf("device-state-update-failed", log.Fields{"device-id": device.Id, "error": err})
 		}
 		if err := oltA.coreProxy.PortsStateUpdate(context.TODO(), device.Id, voltha.OperStatus_UNKNOWN); err != nil {
-			logger.Fatalf("port-update-failed", log.Fields{"device-id": device.Id, "error": err})
+			// Not an error as the previous command will start the process of clearing the OLT
+			logger.Infow("port-update-failed", log.Fields{"device-id": device.Id, "error": err})
 		}
 	}()
 	return nil
@@ -317,22 +289,6 @@
 	return nil, errors.New("start-omci-test-not-implemented")
 }
 
-// GetFlowCount returns the total number of flows presently under this adapter
-func (oltA *OLTAdapter) GetFlowCount() int {
-	oltA.lock.Lock()
-	defer oltA.lock.Unlock()
-
-	return len(oltA.flows)
-}
-
-// ClearFlows removes all flows in this adapter
-func (oltA *OLTAdapter) ClearFlows() {
-	oltA.lock.Lock()
-	defer oltA.lock.Unlock()
-
-	oltA.flows = map[uint64]*voltha.OfpFlowStats{}
-}
-
 func (oltA *OLTAdapter) Get_ext_value(deviceId string, device *voltha.Device, valueflag voltha.ValueType_Type) (*voltha.ReturnValues, error) { // nolint
 	_ = deviceId
 	_ = device
diff --git a/rw_core/mocks/adapter_onu.go b/rw_core/mocks/adapter_onu.go
index 5f4a5e6..217f01d 100644
--- a/rw_core/mocks/adapter_onu.go
+++ b/rw_core/mocks/adapter_onu.go
@@ -20,9 +20,6 @@
 	"context"
 	"errors"
 	"fmt"
-	"strings"
-	"sync"
-
 	"github.com/gogo/protobuf/proto"
 	"github.com/opencord/voltha-lib-go/v3/pkg/adapters/adapterif"
 	com "github.com/opencord/voltha-lib-go/v3/pkg/adapters/common"
@@ -30,22 +27,18 @@
 	ic "github.com/opencord/voltha-protos/v3/go/inter_container"
 	of "github.com/opencord/voltha-protos/v3/go/openflow_13"
 	"github.com/opencord/voltha-protos/v3/go/voltha"
+	"strings"
 )
 
 // ONUAdapter represent ONU adapter attributes
 type ONUAdapter struct {
-	flows map[uint64]*voltha.OfpFlowStats
-	lock  sync.Mutex
-	Adapter
+	*Adapter
 }
 
 // NewONUAdapter creates ONU adapter
 func NewONUAdapter(cp adapterif.CoreProxy) *ONUAdapter {
 	return &ONUAdapter{
-		flows: map[uint64]*voltha.OfpFlowStats{},
-		Adapter: Adapter{
-			coreProxy: cp,
-		},
+		Adapter: NewAdapter(cp),
 	}
 }
 
@@ -116,9 +109,7 @@
 			logger.Fatalf("getting-device-failed-%s", err)
 		}
 
-		if err = onuA.updateDevice(d); err != nil {
-			logger.Fatalf("saving-device-failed-%s", err)
-		}
+		onuA.updateDevice(d)
 	}()
 	return nil
 }
@@ -168,9 +159,7 @@
 			logger.Warnw("device-state-update-failed", log.Fields{"deviceId": device.Id, "error": err})
 			return
 		}
-		if err := onuA.updateDevice(cloned); err != nil {
-			logger.Fatalf("saving-device-failed-%s", err)
-		}
+		onuA.updateDevice(cloned)
 	}()
 	return nil
 }
@@ -195,53 +184,18 @@
 		if err := onuA.coreProxy.DeviceStateUpdate(context.TODO(), cloned.Id, cloned.ConnectStatus, cloned.OperStatus); err != nil {
 			logger.Fatalf("device-state-update-failed", log.Fields{"deviceId": device.Id, "error": err})
 		}
-		if err := onuA.updateDevice(cloned); err != nil {
-			logger.Fatalf("saving-device-failed-%s", err)
-		}
+
+		onuA.updateDevice(cloned)
 	}()
 	return nil
 }
 
-// Update_flows_incrementally mocks the incremental flow update
-func (onuA *ONUAdapter) Update_flows_incrementally(device *voltha.Device, flows *of.FlowChanges, groups *of.FlowGroupChanges, flowMetadata *voltha.FlowMetadata) error { // nolint
-	onuA.lock.Lock()
-	defer onuA.lock.Unlock()
-
-	if flows.ToAdd != nil {
-		for _, f := range flows.ToAdd.Items {
-			onuA.flows[f.Id] = f
-		}
-	}
-	if flows.ToRemove != nil {
-		for _, f := range flows.ToRemove.Items {
-			delete(onuA.flows, f.Id)
-		}
-	}
-	return nil
-}
-
 // Start_omci_test begins an omci self-test
 func (onuA *ONUAdapter) Start_omci_test(device *voltha.Device, request *voltha.OmciTestRequest) (*ic.TestResponse, error) { // nolint
 	_ = device
 	return &ic.TestResponse{Result: ic.TestResponse_SUCCESS}, nil
 }
 
-// GetFlowCount returns the total number of flows presently under this adapter
-func (onuA *ONUAdapter) GetFlowCount() int {
-	onuA.lock.Lock()
-	defer onuA.lock.Unlock()
-
-	return len(onuA.flows)
-}
-
-// ClearFlows removes all flows in this adapter
-func (onuA *ONUAdapter) ClearFlows() {
-	onuA.lock.Lock()
-	defer onuA.lock.Unlock()
-
-	onuA.flows = map[uint64]*voltha.OfpFlowStats{}
-}
-
 func (onuA *ONUAdapter) Get_ext_value(deviceId string, device *voltha.Device, valueflag voltha.ValueType_Type) (*voltha.ReturnValues, error) { // nolint
 	_ = deviceId
 	_ = device