Setting an Astroneer whitelist means that players can only join if authorized by an owner/admin. This is done by designating a Steam display name, which the server grants to the first person to use that name. This is a significantly more secure method than server passwords, as entering the server requires an admin to be present. This makes whitelisting an excellent option for those who only want to play with a handful of specific friends.
Note: Setting up a server Whitelist requires Owner/Admin Permissions.
1. Join the server.
2. Go to the Server Admin tab.
3. Check the Allow Only Whitelisted Players box.
4. Click Add Player to Whitelist to start adding players.
5. Enter the player's Steam Display Name, then choose Whitelist Player.