If you have a cluster it is not important in which node you are connected.
Usually in to solve this typical problem it is enough to configure a simple load-balancer and connect the clients to the L.B.
clients-----> LB ------> rabbitmq(s) instances cluster.
EDIT:
Load balancer as HAPROXY or for example http://crossroads.e-tunity.com/ they are light and simple to use.
I'd like to add also this: RabbitMQ Client connect to several hosts