Method and apparatus for making a cluster of computers appear as a single host on a network

A method for routing incoming messages across a boundary of a cluster of computer nodes, the cluster connected to one or more networks, comprising the steps of:

• reading a software communication protocol number in an IP message header to recognize the incoming message as a software communication protocol port type message, the IP message header being on a message with a destination address of a gateway within the cluster of computer nodes;
• locating and reading a software communication protocol port number in the message header of the software communication protocol port type message;
• matching both the software communication protocol port number and the software communication protocol number to an entry in a message switch memory, the matched software communication protocol port number entry being associated with a port specific function which selects a routing destination for the message from a plurality of possible destinations, the destination being a computer node in the cluster;
• and
• routing the message to the computer node destination.

An apparatus for routing messages across a boundary of a cluster of computers on a network, comprising:

• two or more computers connected together by an interconnect in a cluster, each computer being a node of the cluster;
• one or more computer nodes in the cluster being a gateway node to the cluster, the gateway node being connected to the network at a cluster boundary and having a software communication protocol address on the network, the protocol address being the address of the gateway and the cluster;
• a message switch, residing in the gateway node which matches both a message software communication protocol number and destination software communication protocol port number of the message coming into the cluster from the network to an entry in a table in the message switch memory;
• and
• one or more routing functions, residing in the message switch table, one of the routing functions associated with the matched table entry which is used for directing messages crossing the cluster boundary into the cluster to a destination node within the cluster, the destination node being determined by the message switch using information on the message.