I have just started using KnoppixCluster and hope to setup a firewall using KnoppixCluster. How do I go about doing it?

I am hoping to use it with the failover function with 3 PCs so that should anyone of my machines fail, the other will take over. Is this architecture possible?

I am a newbie and do not know much about using Knoppix.

I welcome all possible suggestions and is grateful for any reply.