Alien Swarm: How to make a server for more than 4 people?

Question

I know there are Alien Swarm dedicated servers for 5 or 6 players.

How do I create a game for more than 4 people?

It may be by listen or dedicated server.

Answer 1

As I already mentioned in the comments on badp's answer, the standard campaign maps do not support it, so there's no telling where you'll end up without modifying it.

However, as in any source game, you can do this by adding -maxplayers 6 to the SRCDS command-line. 6 is a limit hard-coded into the game.

You can also try entering maxplayers 6 in the `Developer Console for a listen server, but I'm not sure whether that works.

If 6 doesn't work, try entering a higher value like 10, it should clamp to 6.

Answer 2

With a server-side mod, you can have up to 10 player slots. However, only five will be able to play - this is hard-coded limit in the game.

There is a mod which allows for up to 8 players, but it requires both the server and all the clients to use custom .dll's (you cannot join normal servers using these dlls, so make sure to backup the default ones!). Of course, since it relies on replacing dlls, future alien swarm updates may break it.

Answer 3

Without modding anything -- the default campaign only allows for 4 players. Custom campaigns, however, have the option to allow up to 5 people in a single mission.