If you see an error that Prompt is connected to mosh-server and is waiting for UDP traffic, something is blocking UDP communication between Prompt and the destination server.

There are a variety of reasons that UDP traffic can be blocked, but the most common culprits are typically firewall rules, port forwarding, or a third-party app such as Little Snitch or Lulu.

If you are unfamiliar with configuring these settings, we recommend consulting your system or network administrator before making any changes as they could could break local networking and/or have security implications.

Potential Workaround

If you are unable to change the network settings on your Mac running Prompt, you may want to consider connecting using Eternal Terminal instead of Mosh. ET works entirely over TCP. This makes less optimal then Mosh when connecting over low-bandwidth or high-latency connections, but it’s identical or better to mosh in all other areas. You can connect to an ET server and move between networks, even going WiFi to mobile or vice-versa, and keep the connection. If you don’t specifically need mosh’s excellent support for very slow networks, it might be worth trying ET instead.

Please Note: Both Mosh and Eternal Terminal require specific software to be installed on the destination server. If you are unsure what connection types are supported by your server, please contact your system administrator.