diff --git a/cmd/start.go b/cmd/start.go
index 4e9c6a29..8c5449af 100644
--- a/cmd/start.go
+++ b/cmd/start.go
@@ -141,8 +141,8 @@ var startCmd = &cobra.Command{
 
 func adminRoot() (string, int) {
 	adminRoot := "/yao/"
-	if root, ok := share.App.Optional["adminRoot"].(string); ok && root != "" {
-		root = strings.TrimPrefix(root, "/")
+	if share.App.AdminRoot != "" {
+		root := strings.TrimPrefix(share.App.AdminRoot, "/")
 		root = strings.TrimSuffix(root, "/")
 		adminRoot = fmt.Sprintf("/%s/", root)
 	}