diff --git a/pipeline.go b/pipeline.go
index b3cc44b..dd299ec 100644
--- a/pipeline.go
+++ b/pipeline.go
@@ -31,6 +31,10 @@ type pipelineIsRecoverableErrorFunc func(error) bool
 func pipelineKinesisIsRecoverableError(err error) bool {
 	recoverableErrorCodes := map[string]bool{
 		"ProvisionedThroughputExceededException": true,
+		"InternalFailure":                        true,
+		"Throttling":                             true,
+		"ServiceUnavailable":                     true,
+		//"ExpiredIteratorException":               true,
 	}
 	r := false
 	cErr, ok := err.(*kinesis.Error)
@@ -151,7 +155,7 @@ func (p Pipeline) ProcessShard(ksis *kinesis.Kinesis, shardID string) {
 			l4g.Error("NextShardIterator ERROR: %v", err)
 			break
 		} else {
-			//time.Sleep(5 * time.Second)
+			time.Sleep(5 * time.Second)
 		}
 
 		if p.Buffer.ShouldFlush() {
diff --git a/pipeline_test.go b/pipeline_test.go
new file mode 100644
index 0000000..3629f05
--- /dev/null
+++ b/pipeline_test.go
@@ -0,0 +1,41 @@
+package connector
+
+import (
+	"fmt"
+	"net"
+	"testing"
+
+	"github.com/ezoic/go-kinesis"
+)
+
+func Test_isRecoverableError(t *testing.T) {
+
+	testCases := []struct {
+		err           error
+		isRecoverable bool
+	}{
+		{err: &kinesis.Error{Code: "ProvisionedThroughputExceededException"}, isRecoverable: true},
+		{err: &kinesis.Error{Code: "Throttling"}, isRecoverable: true},
+		{err: &kinesis.Error{Code: "ServiceUnavailable"}, isRecoverable: true},
+		{err: &kinesis.Error{Code: "ExpiredIteratorException"}, isRecoverable: false},
+		{err: &net.OpError{Err: fmt.Errorf("connection reset by peer")}, isRecoverable: true},
+		{err: &net.OpError{Err: fmt.Errorf("unexpected error")}, isRecoverable: false},
+		{err: fmt.Errorf("an arbitrary error"), isRecoverable: false},
+
+		//"InternalFailure":                        true,
+		//"Throttling":                             true,
+		//"ServiceUnavailable":                     true,
+		////"ExpiredIteratorException":               true,
+		//{err: *kinesis.Error{Code:""}}
+	}
+
+	for idx, tc := range testCases {
+
+		p := Pipeline{}
+		isRecoverable := p.isRecoverableError(tc.err)
+		if isRecoverable != tc.isRecoverable {
+			t.Errorf("test case %d: isRecoverable expected %t, actual %t, for error %+v", idx, tc.isRecoverable, isRecoverable, tc.err)
+		}
+
+	}
+}