Method and system for dispatching client sessions within a cluster of servers connected to the world wide web

• US 6,779,017 B1
• Filed: 12/29/1999
• Issued: 08/17/2004
• Est. Priority Date: 04/29/1999
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Thubert, Pascal, Lamberton, Marc, Levy-Abegnoli, Eric, Montagnon, Eric
• Primary Examiner(s): Geckil, Mehmet B.
• Application Number:
  US09/473,613
• Time in Patent Office: 1,693 Days
• Field of Search: 709/105, 709/203, 709/217, 709/238, 718/105
• US Class Current: 709/203
• CPC Class Codes: G06F 2209/5016 Session
• CPC Class Codes: G06F 9/505 considering the load
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming
• CPC Class Codes: H04L 61/35 involving non-standard use of addresses for implementing network functionalities, e.g. coding subscription information within the address or functional addressing, i.e. assigning an address to a function
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30
• CPC Class Codes: H04L 67/1029 using data related to the state of servers by a load balancer
• CPC Class Codes: H04L 67/1038 Load balancing arrangements to avoid a single path through a load balancer
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

Load balancing of client transactions, for the duration of a client session, in a Web site is implemented by a cluster of servers. An initial request in each client session is sent to the site load balancer, thus, greatly enhancing the capability of the site to accept new session requests. All subsequent requests from a client are forwarded directly to the server first selected so that the sessions cannot be later broken by the load balancer.

Claims

1. A method for preserving load balancing of client transactions for duration of a client session in a Web site comprising a plurality of servers and including a load balancer accessed from a plurality of clients, said method comprising the steps of:

receiving an initial request from a client at said load balancer, wherein the initial request is the only request received by said load balancer from said client for duration of the client session;

said load balancer selecting a particular server from among said plurality of servers;

forwarding said initial request to said particular server;

issuing from said particular server, towards said client, a response uniquely referencing said particular server; and

directly forwarding all subsequent requests from said client to said uniquely referenced particular server, wherein said step of issuing a response from said particular server further comprises before said client initial request is honored, issuing a redirection command to said client including a unique reference of said particular server.

2. The method according to claim 1 wherein:

said response from said particular server self-contains a unique reference of said selected server.

3. The method according to claim 1, wherein the client session is processed by said particular server until the session is ended by said client.

4. A system for preserving load balancing of client transactions for duration of a client session in a Web site comprising a plurality of servers and including a load balancer accessed from a plurality of clients, said system comprising:

means for receiving an initial request from a client at said load balancer, wherein the initial request is the only request received by said load balancer from said client for duration of the client session;

said load balancer selecting a particular server from among said plurality of servers;

means for forwarding said initial request to said particular server;

means for issuing from said particular server, towards said client, a response uniquely referencing said particular server; and

means for directly forwarding all subsequent requests from said client to said uniquely referenced particular server, wherein means for issuing a response from said particular server further comprises before said client initial request is honored, means for issuing a redirection command to said client including a unique reference of said particular server.

5. A computer program product recorded on computer readable media for preserving load balancing of client transactions for duration of a client session in a Web site comprising a plurality of servers and including a load balancer accessed from a plurality of clients, said program product comprising:

computer readable means for receiving an initial request from a client at said load balancer, wherein the initial request is the only request received by said load balancer from said client for duration of the client session;

said load balancer selecting a particular server from among said plurality of servers;

computer readable means for forwarding said initial request to said particular server;

computer readable means for issuing from said particular server, towards said client, a response uniquely referencing said particular server; and

computer readable means for directly forwarding all subsequent requests from said client to said uniquely referenced particular server, wherein computer readable means for issuing a response from said particular server further comprises before said client initial request is honored, computer readable means for issuing a redirection command to said client including a unique reference of said particular server.

6. A method for processing requests directed towards a cluster of servers, the method comprising:

receiving an initial request from the client at a load balancer;

sending, by the load balancer, the request to a particular server from the plurality of servers; and

returning a response, by the particular server, to the client, wherein the response includes information uniquely referencing the particular server, wherein subsequent requests bypass the load balancer and are sent to the particular server from the client using the information, wherein the response is a redirection command containing the information.

7. The method of claim 6, wherein the information includes at least one of an IP address and a DNS name for the particular server.

8. The data processing system of claim 6, wherein the information includes at least one of an IP address and a DNS name for the particular server.

9. The computer program product of claim 6, wherein the information includes at least one of an IP address and a DNS name for the particular server.

10. A server system comprising:

a load balancer; and

a plurality of servers, wherein the load balancer receives an initial request from a client and sends the request to a particular server from a plurality of servers and wherein the particular server returns a response to the client in which the response includes information uniquely referencing the particular server such that subsequent requests are sent to the particular server from the client using the information in which the subsequent requests bypass the load balancer, wherein the response is a redirection command containing the information.

11. A data processing system for processing requests directed towards a cluster of servers, the data processing system comprising:

a bus system;

a communications unit connected to the bus system;

a memory connected to the bus system, wherein the memory includes a set of instructions; and

a processing unit connected to the bus system, wherein the processing unit executes the set of instructions to receive an initial request from the client at a load balancer;

send, by the load balancer the request to a particular server from the plurality of servers; and

return a response, by the particular server, to the client in which the response includes information uniquely referencing the particular server in which subsequent requests bypass the load balancer and are sent to the particular server from the client using the information, wherein the response is a redirection command containing the information.

12. A computer program product in a computer readable medium for processing requests directed towards a cluster of servers, the computer program product comprising:

first instructions for receiving an initial request from the client at a load balancer;

second instructions for sending, by the load balancer, the request to a particular server from the plurality of server; and

third instructions for returning a response, by the particular server, to the client, wherein the response includes information uniquely referencing the particular server, wherein subsequent requests bypass the load balancer and are sent to the particular server from the client using the information, wherein the response is a redirection command containing the information.