Server failover using IPV6 mobility features

• US 8,341,295 B1
• Filed: 03/30/2012
• Issued: 12/25/2012
• Est. Priority Date: 10/29/2004
• Status: Active Grant

• Current Assignee: Akamai Technologies, Inc.
• Original Assignee: Akamai Technologies, Inc.
• Inventors: Liu, Zaide, Day, Richard David, Swildens, Eric Sven-Johan
• Primary Examiner(s): WON, MICHAEL YOUNG
• Application Number:
  US13/435,417
• Time in Patent Office: 270 Days
• Field of Search: 709/203, 709/219, 709/224, 709/226, 709/244
• US Class Current: 709/244
• CPC Class Codes: H04L 2463/101 applying security measures for digital rights management
• CPC Class Codes: H04L 63/102 Entity profiles
• CPC Class Codes: H04L 63/12 Applying verification of the received information cryptographic mechanisms or cryptographic arrangements for data integrity or data verification H04L9/32

Abstract

Techniques are provided for using the mobility support features of IPv6 to allow client and server nodes to communicate without the continuing intervention of a load-balancing node that selected the server node. A load-balancing node intercepts a TCP SYN packet addressed to a virtual IP address. The load-balancing node selects a server node from among multiple server nodes, and sends the packet toward the server node. The server node sends an IPv6 packet toward the client node. The packet contains a Binding Update option that specifies the virtual IP address as a Home Address. This information causes the client node to replace destination addresses in outgoing IP packets so that packets that the client node would have sent toward the virtual IP address are sent toward the selected server node'"'"'s IP address instead. Consequently, the IP packets are routed toward the selected server node instead of the load-balancing node.

Claims

1. A method of providing server failover operative in a computer network having a plurality of nodes that are implemented by computer systems and that include a plurality of server nodes, the method comprising:

(A) determining, at a given node, that a given server node is in a failed condition;

(B) while the given server node is determined to be in the failed condition, the given node;

(i) receiving a first internet protocol (IP) packet from a client node, the first IP packet being addressed to an IP address associated with the given server node;

(ii) sending, to the client node, an IPv6 Mobility Header that includes a binding update option with a lifetime field value of zero;

(iii) receiving a second IP packet from the client node, the second IP packet being addressed to an IP address associated with the given node;

(iv) selecting a server node (the “

selected server node”

) other than the given server node; and

,

(v) sending the second IP packet to the selected server node.

2. The method of claim 1, wherein the given node is a load-balancing node that performs load-balancing across a set of server nodes that includes the given server node and the selected server node.

3. The method of claim 1, further comprising:

the given node advertising to one or more routing nodes that the given server node IP address is reachable through or associated with the given node, so as to enable the given node to intercept the first IP packet.

4. The method of claim 1, wherein the IPv6 Mobility Header is included in an IP packet sent from the given node to the client node.

5. The method of claim 4, wherein the IP packet with the IPv6 Mobility Header includes a TCP reset packet.

6. The method of claim 1, wherein the IP address associated with the given node is a virtual IP address.

7. The method of claim 1, wherein the given node sends the second IP packet to the selected server node by encapsulating the second IP packet within another IP packet and sending the another IP packet to the selected server node.

8. The method of claim 1, wherein the given server node and the selected server node are each within the same server cluster in a particular geographic location.

9. An apparatus that provides server failover, comprising:

one or more processors and memory holding computer program instructions for execution by the one or more processors;

the computer program instructions, when executed by the one or more processors, causing the apparatus to perform the following steps;

(A) determine that a given server node is in a failed condition;

(B) while the given server node is determined to be in the failed condition;

(i) receive a first internet protocol (IP) packet from a client node, the first IP packet being addressed to an IP address associated with the given server node;

(ii) send, to the client node, an IPv6 Mobility Header that includes a binding update option with a lifetime field value of zero;

(iii) receive a second IP packet from the client node, the second IP packet being addressed to an IP address associated with the apparatus;

(iv) select a server node (the “

selected server node”

) other than the given server node; and

,

(v) send the second IP packet to the selected server node.

10. The apparatus of claim 9, wherein execution of the instructions further will cause the apparatus to perform load-balancing across a set of server nodes that includes the given server node and the selected server node.

11. The apparatus of claim 9, wherein execution of the instructions further will cause the apparatus to advertise to one or more routing nodes that the given server node IP address is reachable through or associated with the apparatus, so as to enable the apparatus to intercept the first IP packet.

12. The apparatus of claim 9, wherein the IPv6 Mobility Header is included in an IP packet sent to the client node from the apparatus.

13. The apparatus of claim 12, wherein the IP packet with the IPv6 Mobility Header includes a TCP reset packet.

14. The apparatus of claim 9, wherein the IP address associated with the apparatus is a virtual IP address.

15. The apparatus of claim 9, wherein execution of the instructions further will cause the apparatus to send the second IP packet to the selected server node by encapsulating the second IP packet within another IP packet and sending the another IP packet to the selected server node.

16. The apparatus of claim 9, wherein the given server node and the selected server node are each within the same server cluster in a particular geographic location.

17. A system that provides server failover, comprising:

a plurality of nodes interconnected via a computer network, each of the nodes having circuitry forming one or more processors and memory holding instructions for execution by the one or more processors to operate the node, the plurality of nodes including a plurality of server nodes;

a given node in the plurality of nodes that;

(A) determines that a given server node is in a failed condition, and

(B) while the given server node is in the failed condition,

(i) receives a first internet protocol (IP) packet from a client node, the first IP packet being addressed to an IP address associated with the given server node;

(ii) sends, to the client node, an IPv6 Mobility Header that includes a binding update option with a lifetime field value of zero;

(iii) receives a second IP packet from the client node, the second IP packet being addressed to an IP address associated with the given node;

(iv) selects a server node (the “

selected server node”

) other than the given server node; and

,

(v) sends the second IP packet to the selected server node.

18. The system of claim 17, wherein the given node is a load-balancing node that performs load-balancing across a set of server nodes that includes the given server node and the selected server node.

19. The system of claim 17, wherein the given node advertises to one or more routing nodes that the given server node IP address is reachable through or associated with the given node, so as to enable the given node to intercept the first IP packet.

20. The system of claim 17, wherein the given server node and the selected server node are each within the same server cluster in a particular geographic location.