Automated server replication

• US 7,373,644 B2
• Filed: 10/02/2001
• Issued: 05/13/2008
• Est. Priority Date: 10/02/2001
• Status: Expired due to Term

• Current Assignee: Sandpiper CDN LLC
• Original Assignee: Level 3 Communications LLC (Lumen Technologies, Inc.)
• Inventors: Aborn, Justin
• Primary Examiner(s): An; Meng-Al T.
• Assistant Examiner(s): Vo; Lilian
• Application Number:
  US09/969,437
• Publication Number:
  US 20030065703A1
• Time in Patent Office: 2,415 Days
• Field of Search: 709/200, 709/223, 709/226, 709/229, 709/227, 709/224, 718/100, 718/104, 718/105
• US Class Current: 718/105
• CPC Class Codes: G06F 9/505 considering the load
• CPC Class Codes: H04L 67/01 Protocols
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• 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 67/1031 Controlling of the operation of servers by a load balancer, e.g. adding or removing servers that serve requests

Abstract

Methods and apparatus for detecting a change in demand for server resources across a load-bearing system having one or more content servers hosting identical content, the load-bearing system being connected to a network of content servers; and automatically modifying the number of content servers on the load-bearing system in response to the change in demand.

Claims

1. A computer implemented method comprising:

detecting a change in demand for server resources across a load-bearing system having a number of content servers hosting identical content, the load-bearing system being connected to a network of content servers, wherein the network comprises at least one other load-bearing system having one or more content servers each assigned a priority level; and

automatically modifying the number of content servers on the load-bearing system in response to the change in demand, wherein automatically modifying the number of content servers on the load-bearing system comprises;

selecting an available content server from a selected one of the at least one other load-bearing system based on a comparison of the priority level assigned to the available content server relative to at least one other content server in the network;

loading identical content onto the selected content server by an image manager in communication with the selected content server;

adding the selected content server to the load-bearing system, wherein all of the content servers on the load-bearing system including the selected content server use the identical hosted content;

detecting a change in demand greater than a pre-configured threshold; and

adding a content server to the load-bearing system if the number of content servers on the load-bearing system is less than a maximum number assigned to the hosted identical content,

wherein the hosted identical content is assigned a priority level of a plurality of priority levels, and wherein selecting an available content server comprises selecting an available content server having a lowest priority level and a highest available load capacity.

2. The method of claim 1, wherein each content server on the network is categorized as active or idle.

3. The method of claim 1, wherein the hosted identical content is assigned a number defining a maximum number of content sewers on the load-bearing system.

4. The method of claim 1, wherein the available content server having a least number of active sessions of the number of content servers is selected.

5. The method of claim 1, wherein the hosted identical content is assigned a number defining a minimum number of content servers on the load-bearing system.

6. The method of claim 1, further comprising:

detecting a negative change in demand greater than a pre-configured threshold; and

removing a content server from the load-bearing system if the number of content servers on the load-bearing system is greater than a minimum number assigned to the hosted identical content.

7. The method of claim 6, wherein removing comprises removing the content server having a highest available load capacity.

8. The method of claim 6, wherein removing comprises removing the content server having a least number of active sessions.

9. A system comprising:

a first network having client servers connected to an Internet;

a second network connected to the Internet, the second network comprising;

content servers connected to a management server, a first subset of the content servers providing a load bearing system, the management server including a means for detecting a change in demand for content server resources across the load-bearing system; and

means for automatically modifying a number of content servers in the first subset of content servers on the load bearing system in response to the change in demand, wherein automatically modifying the number of content servers on the load-bearing system comprises;

selecting an available content server on the Internet;

loading identical content from a management server onto the selected content server by an image manager in communication with the selected content server;

adding the selected content server to the load-bearing system, wherein all of the content servers on the load-bearing system including the selected content server use the identical hosted contents;

detecting a change in demand greater than a pre-configured threshold; and

adding a content server to the load-bearing system if the number of content servers on the load-bearing system is less than a maximum number assigned to the identical hosted content,

wherein the identical hosted content is assigned a priority level of a plurality of priority levels, and wherein selecting an available content server comprises selecting an available content server having a lowest priority level and a highest available load capacity.

10. The system of claim 9, wherein the first subset of content servers uses an identical hosted content.

11. The system of claim 9, wherein the management server includes a means for categorizing each content server as active or idle.

12. The system of claim 9, wherein the management server includes a means for assigning the priority level of the plurality of priority levels to the hosted content.

13. The system of claim 9, wherein the management server includes a means for assigning a number defining the maximum number of content servers on the load-bearing system to the identical hosted content.

14. The system of claim 9, wherein the management server selects the available content server having a least number of active sessions.

15. The system of claim 9, wherein the management server includes a means for assigning a number defining a minimum number of content servers on the load-bearing system to the identical hosted content.

16. The system, of claim 9, wherein the management system further comprises a means for:

detecting a negative change in demand greater than another pre-configured threshold; and

removing a content server from the load-bearing system if the number of content servers on the load-bearing system is greater than a minimum number assigned to the hosted content.

17. The system of claim 16, wherein the management server removes the content server having a highest available load capacity.

18. The system of claim 16, wherein the management server removes the content server having a least number of active sessions.

19. A system comprising:

a network comprising a plurality of content servers,

a plurality of load-bearing systems, wherein each of the load-bearing systems comprises one or more of the plurality of content servers; and

a management server configured to;

identify a load-bearing system with insufficient load capacity,

identify an available content server from one or more idle servers not already allocated to any of the load-bearing systems,

allocate the identified content server to the load-bearing system with insufficient capacity,

cause content to be copied onto the identified content server, wherein the content is identical to content associated with the load-bearing system with insufficient capacity,

detect a change in demand greater than a pre-configured threshold; and

add a content server to the load-bearing system if the number of content servers on the load-bearing system is less than a maximum number assigned to the hosted identical content,

wherein the identical content is assigned a priority level of a plurality of priority levels, and wherein identifying an available content server comprises identifying an available content server having a lowest priority level and a highest available load capacity.

20. The system of claim 19, wherein the management server is further configured to identify an available content server from a plurality of idle content servers already allocated to one of the other load-bearing systems by analyzing priority levels assigned to the plurality of idle content servers.

21. The system of claim 19, wherein each of the plurality of load-bearing systems distributes incoming content requests to associated servers based on a load scheme selected from a group consisting of a load-bearing scheme, a load-balancing scheme, and a load-leveling scheme.

22. The system of claim 19, wherein a notification is sent to a network operator maintaining the network if no content servers are available to be associated with the load-bearing system with insufficient capacity.

23. The system of claim 20, wherein the management server is further configured to identify an available content server allocated with one of the other load-bearing systems by polling each of the plurality of content servers to determine which content server has the highest available load capacity.

24. The system of claim 20, wherein the management server is further configured to identify an available content server associated with one of the other load-bearing systems by polling each of the plurality of content servers to determine which content server has the least number of running processes.

25. The system of claim 19, wherein each of the plurality of load-bearing systems is assigned a minimum number of content servers.

26. The system of claim 25, wherein the minimum number of content servers is assigned based on a priority level of the load-bearing system.

27. The system of claim 19, further comprising an image manager configured to de-allocate a content server from one of the load-bearing systems if the historical demand for service warrants de-allocation of a content server.

28. A method for allocating a number of servers to a plurality of web sites, the method comprising:

allocating one or more servers to each of a plurality of web sites;

for each web site, loading a file having content for implementing the web site onto the one or more servers allocated to the web site;

assigning a priority to each file;

monitoring load capacity on the one or more servers allocated to each web site;

detecting load at the one or more servers allocated to a web site that is greater than a specified threshold;

identifying a server allocated to one of the other web sites that is available to be re-allocated to the web site for which load is detected to be greater than the specified threshold, wherein identifying the server to be re-allocated comprises;

determining whether the file of a server allocated to another of the web sites is assigned a lower priority than the priority assigned to the file loaded on the one or more serves for which load is detected to be greater than the specified threshold; and

determining whether the number of servers allocated to the other web site is greater than a specified minimum number of servers;

if the file of the identified server has a lower priority and the number of servers allocated to the other web site is greater than the specified minimum number of servers, re-allocating the identified server from the web site to the web site for which load is detected to be greater than the specified threshold, wherein re-allocating the identified server comprises;

stopping directing of client requests to the identified server;

loading the file implementing the web site for which load is detected to be greater than the specified threshold onto the identified server; and

changing an Internet protocol address of the identified server to an IP address corresponding to the web site that the identified server is re-allocated to.

29. A computer implemented method comprising:

detecting a change in demand for server resources across a load-bearing system having a number of content servers hosting identical content, the load-bearing system being connected to a network of content servers, wherein the network comprises at least one other load-bearing system having one or more content servers each assigned a priority level; and

automatically modifying the number of content servers on the load-bearing system in response to the change in demand, wherein automatically modifying the number of content servers on the load-bearing system comprises;

selecting an available content server from a selected one of the at least one other load-bearing system based on a comparison of the priority level assigned to the available content server relative to at least one other content server in the network;

loading identical content onto the selected content server by an image manager in communication with the selected content server;

adding the selected content server to the load-bearing system, wherein all of the content servers on the load-bearing system including the selected content server use the identical hosted content;

detecting a change in demand greater than a pre-configured threshold; and

adding a content server to the load-bearing system if the number of content servers on the load-bearing system is less than a maximum number assigned to the hosted identical content,

wherein the hosted identical content is assigned a priority level of a plurality of priority levels, and wherein selecting an available content server comprises selecting an available content server having a lowest priority level and wherein the available content server having a least number of active sessions of the number of content servers is selected.

30. A system comprising:

a first network having client servers connected to an Internet;

a second network connected to the Internet, the second network comprising;

content servers connected to a management server, a first subset of the content servers providing a load bearing system, the management server including a means for detecting a change in demand for content server resources across the load-bearing system; and

means for automatically modifying a number of content servers in the first subset of content servers on the load bearing system in response to the change in demand, wherein automatically modifying the number of content servers on the load-bearing system comprises;

selecting an available content server on the Internet;

loading identical content from a management server onto the selected content server by an image manager in communication with the selected content server;

adding the selected content server to the load-bearing system, wherein all of the content servers on the load-bearing system including the selected content server use the identical hosted content;

detecting a change in demand greater than a pre-configured threshold; and

adding a content server to the load-bearing system if the number of content servers on the load-bearing system is less than a maximum number assigned to the hosted identical content,

wherein the hosted identical content is assigned a priority level of a plurality of priority levels, arid wherein selecting an available content server comprises selecting an available content server having a lowest priority level and wherein the management server selects the available content server having a least number of active sessions.

31. A system comprising:

a network comprising a plurality of content servers,

a plurality of load-bearing systems, wherein each of the load-bearing systems comprises one or more of the plurality of content servers; and

a management server configured to;

identify a load-bearing system with insufficient load capacity,

identify an available content server from one or more idle servers not already allocated to any of the load-bearing systems,

allocate the identified content server to the load-bearing system with insufficient capacity,

cause content to be copied onto the identified content server, wherein the content is identical to content associated with the load-bearing system with insufficient capacity,

detect a change in demand greater than a pre-configured threshold; and

add a content server to the load-bearing system if the number of content servers on the load-bearing system is less than a maximum number assigned to the hosted identical content,

wherein the identical content is assigned a priority level of a plurality of priority levels, and wherein identifying an available content server comprises identifying an available content server having a lowest priority level and wherein the available content server having a least number of active sessions of the number of content servers is selected.