Valheim server hosting: dedicated server or hosting in-game?
There are two ways to play Valheim together, and the difference matters more than it seems. Hosting from inside the game makes your PC the server: switch it off and nobody can play, and the world stands still. A dedicated server keeps running.
Why that difference matters
Valheim is a game about building bases and making progress over a long stretch of time. That is exactly when it hurts if the world only exists while one specific person is online. With your own server everyone continues at their own moment — which is why most groups switch after a few weeks.
Your world file is everything
The entire world lives in two files: a .db and a .fwl. Lose those and everything is gone, bases included. So keep backups — at MC-Node they run automatically, but download one yourself now and then if you have a big project going.
Mods with BepInEx
Valheim mods run on BepInEx and must be installed on both sides: the server and every player, at the same version. One person on a different mod version will hit connection problems. Agree on your mod list in advance.
Players and RAM
Valheim is built for small groups; ten players is the practical ceiling. Memory is modest: 2 GB suits a normal group, 4 GB if you have built extensively or run mods. The world does grow as you explore more of the map.