Load balancer bypass

• US 9,246,998 B2
• Filed: 10/16/2012
• Issued: 01/26/2016
• Est. Priority Date: 10/16/2012
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: Kumar, Hemant, Patel, Parveen Kumar, Bansal, Deepak
• Primary Examiner(s): Gillis, Brian J
• Assistant Examiner(s): GRIJALVA LOBOS, BORIS D
• Application Number:
  US13/652,718
• Publication Number:
  US 20140108655A1
• Time in Patent Office: 1,197 Days
• Field of Search: 709201-203, 709211-212, 709/226, 709235-249
• US Class Current: 1/1
• CPC Class Codes: H04L 12/56 Packet switching systems
• CPC Class Codes: H04L 61/2521 Translation architectures other than single NAT servers
• CPC Class Codes: H04L 67/1038 Load balancing arrangements to avoid a single path through a load balancer
• CPC Class Codes: H04L 67/563 Data redirection of data network streams

Abstract

Bypassing a load balancer that initially appeared in a multi-message flow from a source machine served by a source intermediary and a target machine served on a target intermediary. One or more original network messages (and perhaps just the first) of the flow arrive from the source intermediary at the load balancer, which selects which machine is to be a destination machine, and it turns out selects the destination machine serviced by the destination intermediary. In response to receiving this message, the destination intermediary instructs the source intermediary to transmit subsequent messages in the flow in a manner that bypasses the load balancer. To facilitate this, the source intermediary may modify addressing of subsequent flow messages from the source machine such that they are rerouted to the destination machine without addressing the load balancer.

Claims

1. A computer program product comprising one or more hardware storage devices having stored thereon computer-executable instructions that are structured such that, when executed by one or more processors of a destination intermediary computer system, the computer-executable instructions configure the destination intermediary computer system to redirect a multi-message flow so as to bypass a load balancer, including configuring the destination intermediary computer system to perform at least the following:

receive a source-side message from a load balancer, the source-side message including a virtual network address of the load balancer as a destination and having been received by the load balancer from a source intermediary serving a source machine, the source-side message having been augmented by the load balancer to include a network address of a destination machine that is served by the destination intermediary as a destination for the source-side message;

determine that the source intermediary is to address subsequent network messages that originate from the source machine and that are associated with the same multi-message flow to the destination machine in a manner that bypasses the load balancer; and

based on the determination, instruct the source intermediary to address the subsequent network messages that originate from the source machine and that are associated with the same multi-message flow to the destination machine, including dispatching a destination-side network message to the source intermediary that instructs the source intermediary to modify at least a destination address in the subsequent network messages in a manner that the subsequent network messages bypass the load balancer, and in a manner that, from a perspective of the source machine, the source machine sends the subsequent network messages to the virtual network address of the load balancer and receives any responses from the virtual network address of the load balancer, wherein dispatching the destination-side network message to the source intermediary includes bypassing the load balancer when dispatching the destination-side network message to the source intermediary, and wherein the dispatched destination-side network message is separate from a response from the destination machine to the source-side message.

2. The computer program product in accordance with claim 1, wherein the computer-executable instructions that configure the destination intermediary computer system to instruct the source intermediary also include computer-executable instructions that configure the destination intermediary computer system to access the source-side network message, the source-side network message having a source address that includes a routable device identifier that addresses the source machine.

3. The computer program product in accordance with claim 1, wherein the virtual network address of the load balancer is a virtual IP address that is load balanced across a plurality of destination machines.

4. The computer program product in accordance with claim 1, wherein the computer-executable instructions that configure the destination intermediary computer system to instruct the source intermediary to address subsequent network messages that originate from the source machine and that are associated with the same multi-message flow to the destination machine in the manner that bypasses the load balancer also include computer-executable instructions that configure the destination intermediary to instruct the source intermediary to encapsulate the messages to the destination intermediary.

5. The computer program product in accordance with claim 1, wherein the multi-message flow is at an application level.

6. The computer program product in accordance with claim 1, wherein the multi-message flow is at a network level.

20. The computer program product in accordance with claim 1, wherein the computer-executable instructions are also structured such that they also configure the destination intermediary computer system to pass the source-side message to the destination machine.

7. A method, implemented at a computer system that includes one or more processors, the computer system configured as a destination intermediary, for redirecting a multi-message flow so as to bypass a load balancer, the method comprising:

receiving a source-side message from a load balancer, the source-side message including a virtual network address of the load balancer as a destination and having been received by the load balancer from a source intermediary serving a source machine, the source-side message having been augmented by the load balancer to include a network address of a destination machine that is served by the destination intermediary as a destination for the source-side message;

determining that the source intermediary is to address subsequent network messages that originate from the source machine and that are associated with the same multi-message flow to the destination machine in a manner that bypasses the load balancer; and

based on the determination, instructing the source intermediary to address the subsequent network messages that originate from the source machine and that are associated with the same multi-message flow to the destination machine, including dispatching a destination-side network message to the source intermediary that instructs the source intermediary to modify at least a destination address in the subsequent network messages in a manner that the subsequent network messages bypass the load balancer, and in a manner that, from a perspective of the source machine, the source machine sends the subsequent network messages to the virtual network address of the load balancer and receives any responses from the virtual network address of the load balancer, wherein dispatching the destination-side network message to the source intermediary includes bypassing the load balancer when dispatching the destination-side network message to the source intermediary, and wherein the dispatched destination-side network message is separate from a response from the destination machine to the source-side message.

8. The method in accordance with claim 7, wherein the multi-message flow is at an application level or at a network level.

15. The method in accordance with claim 7, wherein instructing the source intermediary comprises accessing the source-side network message, the source-side network message having a source address that includes a routable device identifier that addresses the source machine.

16. The method in accordance with claim 7, wherein the virtual network address of the load balancer is a virtual IP address that is load balanced across a plurality of destination machines.

17. The method in accordance with claim 7, wherein instructing the source intermediary to address subsequent network messages that originate from the source machine and that are associated with the same multi-message flow to the destination machine in the manner that bypasses the load balancer comprises instructing the source intermediary to encapsulate the messages to the destination intermediary.

18. The method in accordance with claim 7, wherein the multi-message flow is at a network level.

19. The method in accordance with claim 7, further comprising passing the source-side message to the destination machine.

9. A destination intermediary computer system, comprising:

one or more hardware processors; and

one or more hardware storage devices having stored thereon computer-executable instructions that are structured such that, when executed by the one or more processors of the destination intermediary computer system, the computer-executable instructions configure the destination intermediary computer system to redirect a multi-message flow so as to bypass a load balancer, including configuring the destination intermediary computer system to perform at least the following;

receive a source-side message from a load balancer, the source-side message including a virtual network address of the load balancer as a destination and having been received by the load balancer from a source intermediary serving a source machine, the source-side message having been augmented by the load balancer to include a network address of a destination machine that is served by the destination intermediary as a destination for the source-side message;

determine that the source intermediary is to address subsequent network messages that originate from the source machine and that are associated with the same multi-message flow to the destination machine in a manner that bypasses the load balancer; and

based on the determination, instruct the source intermediary to address the subsequent network messages that originate from the source machine and that are associated with the same multi-message flow to the destination machine, including dispatching a destination-side network message to the source intermediary that instructs the source intermediary to modify at least a destination address in the subsequent network messages in a manner that the subsequent network messages bypass the load balancer, and in a manner that, from a perspective of the source machine, the source machine sends the subsequent network messages to the virtual network address of the load balancer and receives any responses from the virtual network address of the load balancer, wherein dispatching the destination-side network message to the source intermediary includes bypassing the load balancer when dispatching the destination-side network message to the source intermediary, and wherein the dispatched destination-side network message is separate from a response from the destination machine to the source-side message.

10. The computer system in accordance with claim 9, wherein the multi-message flow is at an application level or at a network level.

11. The computer system in accordance with claim 9, wherein the computer-executable instructions that configure the destination intermediary computer system to instruct the source intermediary also include computer-executable instructions that configure the destination intermediary computer system to access the source-side network message, the source-side network message having a source address that includes a routable device identifier that addresses the source machine.

12. The computer system in accordance with claim 9, wherein the virtual network address of the load balancer is a virtual IP address that is load balanced across a plurality of destination machines.

13. The computer system in accordance with claim 9, wherein the computer-executable instructions that configure the destination intermediary computer system to instruct the source intermediary to address subsequent network messages that originate from the source machine and that are associated with the same multi-message flow to the destination machine in the manner that bypasses the load balancer also include computer-executable instructions that configure the destination intermediary to instruct the source intermediary to encapsulate the messages to the destination intermediary.

14. The computer system in accordance with claim 9, wherein the computer-executable instructions are also structured such that they also configure the destination intermediary computer system to pass the source-side message to the destination machine.