Distributing workload among DNS servers

• US 20060277278A1
• Filed: 06/06/2005
• Published: 12/07/2006
• Est. Priority Date: 06/06/2005
• Status: Abandoned Application

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Hegde, Nikhil, Narasimhan, Rashmi
• Application Number:
  US11/146,440
• Publication Number:
  US 20060277278A1
• Time in Patent Office: Days
• US Class Current: 709/220
• CPC Class Codes: G06F 9/505 considering the load
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• CPC Class Codes: H04L 61/4552 Lookup mechanisms between a plurality of directories; Synchronisation of directories, e.g. metadirectories
• 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 67/1012 based on compliance of requirements or conditions with available server resources
• CPC Class Codes: H04L 67/1029 using data related to the state of servers by a load balancer
• CPC Class Codes: H04L 67/1034 Reaction to server failures by a load balancer
• CPC Class Codes: H04L 67/1036 Load balancing of requests to servers for services different from user content provisioning, e.g. load balancing across domain name servers

Abstract

A method, apparatus, and computer instructions for managing a domain name system (DNS) translation request transmitted to a group of DNS servers. When a DNS request is received at the first DNS server in the group, the length of the input queue at the first DNS server is determined. If the length of the input queue exceeds a predetermined value, then the DNS request is sent to a second input queue at a second DNS server before the DNS request is added to the first input queue. Consequently, the mechanism of the present invention provides for sending DNS requests to whichever DNS server in the group has the shortest queue length and balancing DNS requests across a group of DNS servers

Claims

1. A method in a data processing system for managing a DNS request, said method comprising:

receiving a DNS request at a first DNS server;

determining a length of a first input queue of DNS requests at the first DNS server; and

if the length of the first input queue exceeds a predetermined value, transferring the DNS request to a second DNS server before the DNS request times out.

2. The method of claim 1 further comprising:

after transferring the DNS request to the second DNS server, determining a length of a second input queue of DNS requests at the second DNS server; and

if the length of the second input queue exceeds a predetermined value, transferring the DNS request to a third DNS server before the DNS request times out.

3. The method of claim 1 further comprising:

after transferring the DNS request to the third DNS server, determining a length of a third input queue of DNS requests at the third DNS server; and

if the length of the third input queue exceeds a predetermined value, then before-the DNS request times out, managing the DNS request by performing a task selected from the group consisting of;

retaining the DNS request at the third DNS server, transferring the DNS request to the second DNS server, and transferring the DNS request to the first DNS server.

4. The method of claim 3 wherein the task is selected by determining a current length of the queue at the first DNS server, a current length of the queue at the second DNS server, and a current length of the queue at the third DNS server, and thereafter selecting the task based on which DNS server has the shortest current queue.

5. The method of claim 4 further comprising:

dropping the DNS request if the first DNS server, the second DNS server, and the third DNS server each fail to process the DNS request.

6. The method of claim 1 further comprising:

processing the DNS request at the first DNS server if the length of the first input queue is less than or equal to the predetermined value.

7. The method of claim 1 further comprising:

processing the DNS request at the second DNS server if the length of the first input queue exceeds the predetermined value.

8. The method of claim 1 wherein the step of transferring is performed before the DNS request is added to the first input queue.

9. A computer program product comprising:

a computer usable medium having computer useable program code for managing a DNS request, said computer program product including;

computer usable program code for receiving a DNS request at a first DNS server;

computer usable program code for determining a length of a first input queue of DNS requests at the first DNS server; and

computer usable program code for, if the length of the first input queue exceeds a predetermined value, transferring the DNS request to a second DNS server before the DNS request times out.

10. The computer program product of claim 9 further comprising:

computer usable program code for, after transferring the DNS request to the second DNS server, determining a length of a second input queue of DNS requests at the second DNS server; and

computer usable program code for, if the length of the second input queue exceeds a predetermined value, transferring the DNS request to a third DNS server before the DNS request times out.

11. The computer program product of claim 9 further comprising:

computer usable program code for, after transferring the DNS request to the third DNS server, determining a length of a third input queue of DNS requests at the third DNS server; and

computer usable program code for, if the length of the third input queue exceeds a predetermined value, then before the DNS request times out, managing the DNS request by performing a task selected from the group consisting of;

retaining the DNS request at the third DNS server, transferring the DNS request to the second DNS server, and transferring the DNS request to the first DNS server.

12. The computer program product of claim 11 further comprising:

computer usable program code for selecting the task by determining a current length of the queue at the first DNS server, a current length of the queue at the second DNS server, and a current length of the queue at the third DNS server, and thereafter selecting the task based on which DNS server has the shortest current queue.

13. The computer program product of claim 12 further comprising:

computer usable program code for dropping the DNS request if the first DNS server, the second DNS server, and the third DNS server each fail to process the DNS request.

14. The computer program product of claim 9 further comprising:

computer usable program code for processing the DNS request at the first DNS server if the length of the first input queue is less than or equal to the predetermined value.

15. The computer program product of claim 9 further comprising:

computer usable program code for processing the DNS request at the second DNS server if the length of the first input queue exceeds the predetermined value.

16. The computer program product of claim 9 wherein the computer usable program code for transferring is adapted such that transferring is performed before the DNS request is added to the first input queue.

17. A data processing system for managing a DNS request, said data processing system comprising:

a bus;

a memory operably connected to the bus, wherein the memory contains a set of instructions;

a processor operably connected to the bus, wherein the processor executes the set of instructions to;

receive a DNS request at a first DNS server;

determine a length of a first input queue of DNS requests at the first DNS server; and

if the length of the first input queue exceeds a predetermined value, transfer the DNS request to a second DNS server before the DNS request times out.

18. The data processing system of claim 17 wherein the processor further executes the instructions to:

after transferring the DNS request to the second DNS server, determine a length of a second input queue of DNS requests at the second DNS server; and

if the length of the second input queue exceeds a predetermined value, transfer the DNS request to a third DNS server before the DNS request times out.

19. The data processing system of claim 17 wherein the processor further executes the instructions to:

after transferring the DNS request to the third DNS server, determine a length of a third input queue of DNS requests at the third DNS server; and

if the length of the third input queue exceeds a predetermined value, then before the DNS request times out, manage the DNS request by performing a task selected from the group consisting of;

retaining the DNS request at the third DNS server, transferring the DNS request to the second DNS server, and transferring the DNS request to the first DNS server.

20. The data processing system of claim 19 wherein the processor further executes the instructions to:

select the task by determining a current length of the queue at the first DNS server, a current length of the queue at the second DNS server, and a current length of the queue at the third DNS server, and thereafter selecting the task based on which DNS server has the shortest current queue.