diff --git a/src/core/main.go b/src/core/main.go
index 2d32c2d57b..854d823878 100755
--- a/src/core/main.go
+++ b/src/core/main.go
@@ -217,12 +217,10 @@ func main() {
 			log.Fatalf("failed to initialize clair database: %v", err)
 		}
 
-		// TODO: change to be internal adapter
 		reg := &scanner.Registration{
 			Name:            "Clair",
 			Description:     "The clair scanner adapter",
 			URL:             config.ClairAdapterEndpoint(),
-			IsDefault:       true,
 			UseInternalAddr: true,
 			Immutable:       true,
 		}
diff --git a/src/pkg/scan/init.go b/src/pkg/scan/init.go
index cbc14c7953..fdf22848b5 100644
--- a/src/pkg/scan/init.go
+++ b/src/pkg/scan/init.go
@@ -15,10 +15,16 @@
 package scan
 
 import (
+	"fmt"
+
 	"github.com/goharbor/harbor/src/common/utils/log"
 	"github.com/goharbor/harbor/src/pkg/q"
-	sc "github.com/goharbor/harbor/src/pkg/scan/api/scanner"
 	"github.com/goharbor/harbor/src/pkg/scan/dao/scanner"
+	sc "github.com/goharbor/harbor/src/pkg/scan/scanner"
+)
+
+var (
+	scannerManager = sc.New()
 )
 
 // EnsureScanner ensure the scanner which specially name exists in the system
@@ -27,13 +33,22 @@ func EnsureScanner(registration *scanner.Registration) error {
 		Keywords: map[string]interface{}{"url": registration.URL},
 	}
 
-	registrations, err := sc.DefaultController.ListRegistrations(q)
+	// Check if the registration with the url already existing.
+	registrations, err := scannerManager.List(q)
 	if err != nil {
 		return err
 	}
 
 	if len(registrations) == 0 {
-		if _, err := sc.DefaultController.CreateRegistration(registration); err != nil {
+		defaultReg, err := scannerManager.GetDefault()
+		if err != nil {
+			return fmt.Errorf("failed to get the default scanner, error: %v", err)
+		}
+
+		// Set the registration to be default one when no default registration exist in the system
+		registration.IsDefault = defaultReg == nil
+
+		if _, err := scannerManager.Create(registration); err != nil {
 			return err
 		}
 
diff --git a/src/pkg/scan/init_test.go b/src/pkg/scan/init_test.go
new file mode 100644
index 0000000000..c2a0a08693
--- /dev/null
+++ b/src/pkg/scan/init_test.go
@@ -0,0 +1,178 @@
+// Copyright Project Harbor Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package scan
+
+import (
+	"testing"
+
+	"github.com/goharbor/harbor/src/pkg/q"
+	"github.com/goharbor/harbor/src/pkg/scan/dao/scanner"
+	sc "github.com/goharbor/harbor/src/pkg/scan/scanner"
+	"github.com/goharbor/harbor/src/pkg/scan/scanner/mocks"
+	"github.com/pkg/errors"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/mock"
+)
+
+type managerOptions struct {
+	registrations   []*scanner.Registration
+	listError       error
+	getError        error
+	getDefaultError error
+	createError     error
+}
+
+func newManager(opts *managerOptions) sc.Manager {
+	if opts == nil {
+		opts = &managerOptions{}
+	}
+
+	data := map[string]*scanner.Registration{}
+	for _, reg := range opts.registrations {
+		data[reg.URL] = reg
+	}
+
+	mgr := &mocks.Manager{}
+
+	listFn := func(query *q.Query) []*scanner.Registration {
+		if opts.listError != nil {
+			return nil
+		}
+
+		url := query.Keywords["url"]
+
+		var results []*scanner.Registration
+		for key, reg := range data {
+			if url == key {
+				results = append(results, reg)
+			}
+		}
+
+		return results
+	}
+
+	getFn := func(url string) *scanner.Registration {
+		if opts.getError != nil {
+			return nil
+		}
+
+		return data[url]
+	}
+
+	getDefaultFn := func() *scanner.Registration {
+		if opts.getDefaultError != nil {
+			return nil
+		}
+
+		for _, reg := range data {
+			if reg.IsDefault {
+				return reg
+			}
+		}
+
+		return nil
+	}
+
+	createFn := func(reg *scanner.Registration) string {
+		if opts.createError != nil {
+			return ""
+		}
+
+		data[reg.URL] = reg
+
+		return reg.URL
+	}
+
+	mgr.On("List", mock.AnythingOfType("*q.Query")).Return(listFn, opts.listError)
+	mgr.On("Get", mock.AnythingOfType("string")).Return(getFn, opts.getError)
+	mgr.On("GetDefault").Return(getDefaultFn, opts.getDefaultError)
+	mgr.On("Create", mock.AnythingOfType("*scanner.Registration")).Return(createFn, opts.createError)
+
+	return mgr
+}
+
+func TestEnsureScanner(t *testing.T) {
+	assert := assert.New(t)
+
+	registrations := []*scanner.Registration{
+		{URL: "reg1"},
+	}
+
+	// registration with the url exist in the system
+	scannerManager = newManager(
+		&managerOptions{
+			registrations: registrations,
+		},
+	)
+	assert.Nil(EnsureScanner(&scanner.Registration{URL: "reg1"}))
+
+	// list registrations got error
+	scannerManager = newManager(
+		&managerOptions{
+			listError: errors.New("list registrations internal error"),
+		},
+	)
+	assert.Error(EnsureScanner(&scanner.Registration{URL: "reg1"}))
+
+	// create registration got error
+	scannerManager = newManager(
+		&managerOptions{
+			createError: errors.New("create registration internal error"),
+		},
+	)
+	assert.Error(EnsureScanner(&scanner.Registration{URL: "reg1"}))
+
+	// get default registration got error
+	scannerManager = newManager(
+		&managerOptions{
+			getDefaultError: errors.New("get default registration internal error"),
+		},
+	)
+	assert.Error(EnsureScanner(&scanner.Registration{URL: "reg1"}))
+
+	// create registration when no registrations in the system
+	scannerManager = newManager(nil)
+	assert.Nil(EnsureScanner(&scanner.Registration{URL: "reg1"}))
+	reg1, err := scannerManager.Get("reg1")
+	assert.Nil(err)
+	assert.NotNil(reg1)
+	assert.True(reg1.IsDefault)
+
+	// create registration when there are registrations in the system
+	scannerManager = newManager(
+		&managerOptions{
+			registrations: registrations,
+		},
+	)
+	assert.Nil(EnsureScanner(&scanner.Registration{URL: "reg2"}))
+	reg2, err := scannerManager.Get("reg2")
+	assert.Nil(err)
+	assert.NotNil(reg2)
+	assert.True(reg2.IsDefault)
+
+	// create registration when there are registrations in the system and the default registration exist
+	scannerManager = newManager(
+		&managerOptions{
+			registrations: []*scanner.Registration{
+				{URL: "reg1", IsDefault: true},
+			},
+		},
+	)
+	assert.Nil(EnsureScanner(&scanner.Registration{URL: "reg3"}))
+	reg3, err := scannerManager.Get("reg3")
+	assert.Nil(err)
+	assert.NotNil(reg3)
+	assert.False(reg3.IsDefault)
+}
diff --git a/src/pkg/scan/scanner/mocks/manager.go b/src/pkg/scan/scanner/mocks/manager.go
new file mode 100644
index 0000000000..15731b986d
--- /dev/null
+++ b/src/pkg/scan/scanner/mocks/manager.go
@@ -0,0 +1,147 @@
+// Code generated by mockery v1.0.0. DO NOT EDIT.
+
+package mocks
+
+import (
+	q "github.com/goharbor/harbor/src/pkg/q"
+	mock "github.com/stretchr/testify/mock"
+
+	scanner "github.com/goharbor/harbor/src/pkg/scan/dao/scanner"
+)
+
+// Manager is an autogenerated mock type for the Manager type
+type Manager struct {
+	mock.Mock
+}
+
+// Create provides a mock function with given fields: registration
+func (_m *Manager) Create(registration *scanner.Registration) (string, error) {
+	ret := _m.Called(registration)
+
+	var r0 string
+	if rf, ok := ret.Get(0).(func(*scanner.Registration) string); ok {
+		r0 = rf(registration)
+	} else {
+		r0 = ret.Get(0).(string)
+	}
+
+	var r1 error
+	if rf, ok := ret.Get(1).(func(*scanner.Registration) error); ok {
+		r1 = rf(registration)
+	} else {
+		r1 = ret.Error(1)
+	}
+
+	return r0, r1
+}
+
+// Delete provides a mock function with given fields: registrationUUID
+func (_m *Manager) Delete(registrationUUID string) error {
+	ret := _m.Called(registrationUUID)
+
+	var r0 error
+	if rf, ok := ret.Get(0).(func(string) error); ok {
+		r0 = rf(registrationUUID)
+	} else {
+		r0 = ret.Error(0)
+	}
+
+	return r0
+}
+
+// Get provides a mock function with given fields: registrationUUID
+func (_m *Manager) Get(registrationUUID string) (*scanner.Registration, error) {
+	ret := _m.Called(registrationUUID)
+
+	var r0 *scanner.Registration
+	if rf, ok := ret.Get(0).(func(string) *scanner.Registration); ok {
+		r0 = rf(registrationUUID)
+	} else {
+		if ret.Get(0) != nil {
+			r0 = ret.Get(0).(*scanner.Registration)
+		}
+	}
+
+	var r1 error
+	if rf, ok := ret.Get(1).(func(string) error); ok {
+		r1 = rf(registrationUUID)
+	} else {
+		r1 = ret.Error(1)
+	}
+
+	return r0, r1
+}
+
+// GetDefault provides a mock function with given fields:
+func (_m *Manager) GetDefault() (*scanner.Registration, error) {
+	ret := _m.Called()
+
+	var r0 *scanner.Registration
+	if rf, ok := ret.Get(0).(func() *scanner.Registration); ok {
+		r0 = rf()
+	} else {
+		if ret.Get(0) != nil {
+			r0 = ret.Get(0).(*scanner.Registration)
+		}
+	}
+
+	var r1 error
+	if rf, ok := ret.Get(1).(func() error); ok {
+		r1 = rf()
+	} else {
+		r1 = ret.Error(1)
+	}
+
+	return r0, r1
+}
+
+// List provides a mock function with given fields: query
+func (_m *Manager) List(query *q.Query) ([]*scanner.Registration, error) {
+	ret := _m.Called(query)
+
+	var r0 []*scanner.Registration
+	if rf, ok := ret.Get(0).(func(*q.Query) []*scanner.Registration); ok {
+		r0 = rf(query)
+	} else {
+		if ret.Get(0) != nil {
+			r0 = ret.Get(0).([]*scanner.Registration)
+		}
+	}
+
+	var r1 error
+	if rf, ok := ret.Get(1).(func(*q.Query) error); ok {
+		r1 = rf(query)
+	} else {
+		r1 = ret.Error(1)
+	}
+
+	return r0, r1
+}
+
+// SetAsDefault provides a mock function with given fields: registrationUUID
+func (_m *Manager) SetAsDefault(registrationUUID string) error {
+	ret := _m.Called(registrationUUID)
+
+	var r0 error
+	if rf, ok := ret.Get(0).(func(string) error); ok {
+		r0 = rf(registrationUUID)
+	} else {
+		r0 = ret.Error(0)
+	}
+
+	return r0
+}
+
+// Update provides a mock function with given fields: registration
+func (_m *Manager) Update(registration *scanner.Registration) error {
+	ret := _m.Called(registration)
+
+	var r0 error
+	if rf, ok := ret.Get(0).(func(*scanner.Registration) error); ok {
+		r0 = rf(registration)
+	} else {
+		r0 = ret.Error(0)
+	}
+
+	return r0
+}