How do I set up a Valheim dedicated server?

Your server's start command and core settings live on the Startup page: server name, world name, and password are set there as startup variables. Valheim requires a password of at least 5 characters; the server will not start without one. Decide on a world name before your first start, since this is the name Valheim uses for the save files it generates and changing it later starts a brand new world rather than renaming the existing one.

The first start takes a few minutes longer than normal, since the server downloads the Valheim dedicated server files before it can generate the world. Watch the Console page for progress; a successful start ends with a line confirming the game server is listening for connections.

Your server is public by default and appears in the in-game server browser under its configured name. If you would rather keep it private, set Public to 0 on the Startup page; a private server will not appear in the browser. Either way, friends can always join directly - give players your server's address and port from the Network page along with the password.

World save files are written to .config/unity3d/IronGate/Valheim/worlds_local - note that is a hidden dotfile path, not the server root, so you will not find it by clicking around from the top level - as a .db and .fwl pair named after your world. Back these up regularly from the Backups page: a corrupted or lost world file cannot be recovered any other way.