Content-Based publish/subscribe systems have recently received an increasing attention. Efficient routing algorithms and self-configuration are two key issues in the area of large-scale content-based publish/subscribe systems. Although many routing algorithms have been proposed, none of them fully exploits multicast to enhance system performance and save network bandwidth. In addition, the vast majority of currently available publish-subscribe middleware has ignored this self-configuration problem. This paper first proposes a hierarchical system model with multicast clustering. Then a hybrid routing algorithm is presented, which can fully exploit multicast in order to reduce the used network bandwidth. Moreover, a multicast clustering replication protocol and a content-based multicast tree protocol are presented for coping with the node or link failures and rebuilding the event dispatcher trees. Experimental results reveal that the system has better routing efficiency and lower cost, and guarantees the self-configuration characteristic.