Session-less load balancing of client traffic across servers in a server group

A method of forwarding incoming client traffic to servers in a group of servers, the method comprising:

• providing a single switch device with a packet forwarding table for providing load balancing across servers in a server group, the packet forwarding table having a plurality of table entries, each table entry mapping a hash value to a server in the server group;
• assigning a virtual IP address and a virtual MAC address to each real server in a real server group, wherein the assigned virtual IP address is the same virtual IP address for each real server in the real server group and the assigned virtual MAC address is the same virtual MAC address for each real server in the real server group;
• receiving a packet from a client system addressed to the virtual IP address and the virtual MAC address;
• computing, by the single switch device, a hash value from a source address in a packet header of the received packet;
• searching, by the single switch device, the packet forwarding table to find a table entry with a hash value that matches the computed hash value and to identify, from the table entry, the server in the server group to which the matching hash value maps;
• and
• forwarding sessionlessly, by the single switch device, the packet to the identified server.

A switch device comprising:

• first and second ports, a first port receiving a packet from a client system, the packet including a packet header with a destination MAC (Media Access Control) address field, a destination IP (Internet Protocol) address field, and a destination service port field;
• a packet forwarding table for providing load balancing across servers in a server group, the packet forwarding table having a plurality of table entries, each table entry mapping a hash value to a server in the server group;
• and
• a frame processor configured to compute a hash value from a combination of data in the destination MAC address, destination IP address, and destination service port fields of the packet header of the received packet, search the packet forwarding table to find a table entry with a hash value that matches the computed hash value and to identify the server in the server group to which the matching hash value maps, and forward sessionlessly the packet through the second port to the identified server in the server group.

A switch device, comprising:

• first and second ports, a first port receiving a packet from a client system addressed to a virtual IP address and a virtual MAC address, the virtual IP address and the virtual MAC address being assigned to each real server in a real server group with which the switch device is in communication, the assigned virtual IP address being the same virtual IP address for each real server in the real server group and the assigned virtual MAC address being the same virtual MAC address for each real server in the real server group;
• a packet forwarding table for providing load balancing across servers in a server group, the packet forwarding table having a plurality of table entries, each table entry mapping a hash value to a server in a server group;
• and
• a frame processor configured to compute a hash value from a source address in a packet header of the received packet, search the packet forwarding table to find a table entry with a hash value that matches the computed hash value and to identify the server in the server group to which the matching hash value maps, and forward sessionlessly the packet through the second port to the identified server in the server group.