diff --git a/cbdatasource/cbdatasource.go b/cbdatasource/cbdatasource.go
index d40f695..3067e7a 100644
--- a/cbdatasource/cbdatasource.go
+++ b/cbdatasource/cbdatasource.go
@@ -253,6 +253,8 @@ type BucketDataSourceStats struct {
 	TotWorkerAuth       uint64
 	TotWorkerAuthErr    uint64
 	TotWorkerAuthFail   uint64
+	TotWorkerSelBktFail uint64
+	TotWorkerSelBktOk   uint64
 	TotWorkerAuthOk     uint64
 	TotWorkerUPROpenErr uint64
 	TotWorkerUPROpenOk  uint64
@@ -352,7 +354,8 @@ type bucketDataSource struct {
 	bucketName string
 	bucketUUID string
 	vbucketIDs []uint16
-	auth       couchbase.AuthHandler
+	auth       couchbase.AuthHandler // auth for couchbase
+	authMemchd couchbase.AuthHandler // auth for memcached
 	receiver   Receiver
 	options    *BucketDataSourceOptions
 
@@ -392,6 +395,7 @@ func NewBucketDataSource(
 	bucketUUID string,
 	vbucketIDs []uint16,
 	auth couchbase.AuthHandler,
+	authMemchd couchbase.AuthHandler,
 	receiver Receiver,
 	options *BucketDataSourceOptions) (BucketDataSource, error) {
 	if len(serverURLs) < 1 {
@@ -416,6 +420,7 @@ func NewBucketDataSource(
 		bucketUUID: bucketUUID,
 		vbucketIDs: vbucketIDs,
 		auth:       auth,
+		authMemchd: authMemchd,
 		receiver:   receiver,
 		options:    options,
 
@@ -720,8 +725,8 @@ func (d *bucketDataSource) worker(server string, workerCh chan []uint16) int {
 	defer client.Close()
 	atomic.AddUint64(&d.stats.TotWorkerConnectOk, 1)
 
-	if d.auth != nil {
-		user, pswd, _ := d.auth.GetCredentials()
+	if d.authMemchd != nil {
+		user, pswd, _ := d.authMemchd.GetCredentials()
 		if user != "" {
 			atomic.AddUint64(&d.stats.TotWorkerAuth, 1)
 			res, err := client.Auth(user, pswd)
@@ -738,6 +743,13 @@ func (d *bucketDataSource) worker(server string, workerCh chan []uint16) int {
 			}
 			atomic.AddUint64(&d.stats.TotWorkerAuthOk, 1)
 		}
+		_, err = client.SelectBucket(d.bucketName)
+		if err != nil {
+			atomic.AddUint64(&d.stats.TotWorkerSelBktFail, 1)
+			d.receiver.OnError(fmt.Errorf("worker select bucket err: %v", err))
+			return 0
+		}
+		atomic.AddUint64(&d.stats.TotWorkerSelBktOk, 1)
 	}
 
 	uprOpenName := d.options.Name