Context:
I have a system that will need to support 20,000 connected chat users spread over 100 chat rooms. During performance testing I've found that I can get up to 6,000 connected users on a single box before I get a crash dump, so in production I'll probably go with four servers in a cluster.
My Question:
I understand that a chatroom is bound to a server node, so that if the node dies the chatroom disappears with it and the users no longer belong to the room. Is there a way to "replicate" a chatroom over to another node so that users who are left behind are moved to the replicated room? If not, what do you do to keep continuity for the users?