Do people need to subscribe to mod in order to play on server with that mod?

[Boo]

I would like to enable one mod on my server, but I am not sure, if this could theoretically prevent people from joining the server? Do they need to download the mod, or it's downloaded from server? It's a linux server, so I can't use steam to install the mod, I need to copy the files by hand, which means that in future if someone was subscribed to mod and new version was released, it would be auto updated for that person, but old version of mod would be on server. Would there be problem connecting to server if I did that? Or is it possible to have 2 versions of same mod installed on client?

[fflam]

Mods from the workshop are automatically subscribed to and downloaded. the only exception i have found is the center map DLC, it tried to download it, but seems to hang. so for that they have to go to the store page and get the DLC in order to connect.

[Kogadins]

You cannot have different Version for Client and Server. If the Mod Version for the Client is newer than the Server Version, the Client cannot join. You would need to Update the Server Mod Version then. If the Server Version is newer than the Client Version, the Client would start Downloading the newest Version.

As soon as a Player is joining a Server, the Client will subscribe to all Mods that are active on the Server the Player is joining. Only exception is the Center DLC.