What publishing does
Gives an instance an address that works from any computer, anywhere.
On this page 3 sections
MSL's normal SSH gets you into an instance from this Mac. Publishing gets somebody in from anywhere — a laptop on another network, a phone, a colleague's machine.
That turns an instance into a small server: something you leave running and reach when you need it.
msl public expose UbuntuYou get back an address and the command to use it:
abinaash@mlisv-218-212-52-212.run.pinggy-free.link:38003Anyone with that address, and a key you've allowed, can log in with ordinary ssh. They need no account, no MSL, and nothing installed — which is the whole point of doing it this way.
How it works#
The tunnel runs on your Mac, not inside the instance. MSL already reaches the guest's SSH port on your local network, so it forwards that through a relay and out to the internet. The instance itself is never changed to make this work, and nothing is installed in it.
What it costs#
By default MSL uses a free public relay, which means two honest limits:
| Free relay | Your own server | |
|---|---|---|
| Address | Random, and changes | Yours, and stays |
| Session | About an hour, then renewed at a new address | No limit |
| Needs | Nothing | A machine you can already ssh to |
The free relay is right for "let me show you this". For something you actually depend on, publish through a server you own — see Through your own server.
Just reaching it from this Mac#
If you only want a server inside Linux to open in a browser on this Mac, you do not need any of this — see Reaching a port inside Linux.