If you find an old backup of a 0.14.3 server on a forgotten hard drive, boot it up. Listen to the sound of a dozen players mining cobblestone and complaining about latency. Then, for your own safety, shut it down and migrate to a modern server.
: If you want friends to join from outside your house, you must open port 19132 (UDP) in your router settings. ⚠️ 4. Key Limitations to Remember pocketmine 0.14.3