diff --git a/src/plugins/IORedisPlugin.ts b/src/plugins/IORedisPlugin.ts
index d4d2c76..d7ce3aa 100644
--- a/src/plugins/IORedisPlugin.ts
+++ b/src/plugins/IORedisPlugin.ts
@@ -49,7 +49,7 @@
       span.layer = SpanLayer.CACHE;
       span.peer = host;
       span.tag(Tag.dbType('Redis'));
-      span.tag(Tag.dbInstance(`${this.condition.select}`));
+      span.tag(Tag.dbInstance(`${this.condition?.select ?? host}`));
 
       try {
         const ret = wrapPromise(span, _original.apply(this, args));