diff --git a/metric/metric.go b/metric/metric.go
index f7ad057..c520214 100644
--- a/metric/metric.go
+++ b/metric/metric.go
@@ -16,8 +16,8 @@ import (
 )
 
 const (
-	METRIC_HEAD_INLINE = byte(1)
-	METRIC_TAIL_INLINE = byte(2)
+	METRIC_HEAD_INLINE = byte(14)
+	METRIC_TAIL_INLINE = byte(15)
 )
 
 type MetricType int
diff --git a/server.go b/server.go
index 5578566..d49abcc 100644
--- a/server.go
+++ b/server.go
@@ -31,6 +31,15 @@ import (
 	"go.mongodb.org/mongo-driver/bson/primitive"
 )
 
+func init() {
+	gob.Register(map[string]any{})
+	gob.Register(primitive.A{})
+	gob.Register(primitive.M{})
+	gob.Register(primitive.D{})
+	gob.Register(primitive.ObjectID{})
+	gob.Register([]any{})
+}
+
 const (
 	// HTTPStatusReloginRequired : http status를 이걸 받으면 클라이언트는 로그아웃하고 로그인 화면으로 돌아가야 한다.
 	HTTPStatusReloginRequired = 599