The most common way of achieving this consensus is to make a single node the leader, and put it in charge of making all the decisions. That works fine as long as you don’t mind funneling all requests through a single node (even if the client is on the other side of the world), and as long as that node doesn’t fail. If you need to tolerate the leader failing, you’re back at the consensus problem again (see “Single-leader replication and consensus”).
