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@@ -359,7 +359,8 @@ https://github.com/rustdesk/rustdesk/discussions/6398#discussioncomment-9065991
 
 # Connecting
 
-Ensure your relay server (`hbbr` which uses TCP `21117` port) is running on the same server of `hbbs`.
+- Ensure your relay server (`hbbr` which uses TCP `21117` port) is running on the same server of `hbbs`.
+- Ensure the controlled side can connect to `hbbs` with tcp `21116` port (`telnet server-ip 21116`)
 
 ![image](https://github.com/user-attachments/assets/90c51c37-8ec4-4bcf-96e3-e8d21b60c878)