Directory-based failure recovery and load balancing system

• US 6,298,451 B1
• Filed: 11/02/1999
• Issued: 10/02/2001
• Est. Priority Date: 11/02/1999
• Status: Expired due to Fees

• Current Assignee: Idini
• Original Assignee: Idini
• Inventors: Lin, Horng-Dar
• Primary Examiner(s): LE, DIEU MINH T
• Application Number:
  US09/432,491
• Time in Patent Office: 700 Days
• Field of Search: 714/4, 714/2, 714/15, 714/16, 714/34, 714/47, 709/105, 709/106, 709/203
• US Class Current: 714/4.2
• CPC Class Codes: G06F 2209/5015 Service provider selection
• CPC Class Codes: G06F 9/5055 considering software capabilities, i.e. software resources associated or available to the machine

Abstract

A method is described wherein tasks are managed in a hierarchical fashion using multiple directories servers and multiple resource management servers each of the directory servers and management servers having either distinct or overlapping responsibilities. The method includes determining that a client computer requires that a first task be performed by a server computer configured to handle that first task, causing the client computer to query the directory server to determine which servers within the plurality of servers is configured to handle the first task, causing the directory server to determine at least one server within the plurality of servers which is configured to handle the first task, and to transmit specific information about the at least one server to the client computer. The method proceeds with causing the client computer to transmit a task request to a preferred server chosen from the at least one servers.

Claims

1. In a server system having a client computer, and a plurality of servers, at least one of the servers within said plurality being configured to operate a directory service, and at least one of the servers within said plurality being configured to operate a resource management service, each of said servers within said plurality configured to perform overlapping subsets of tasks chosen from a master group of tasks, a method for performing the assignment of tasks comprising:

determining that the client computer requires that a first task be performed by a server computer configured to handle that task;

causing the client computer to query the directory server to determine which of a set of servers within said plurality of servers is configured to handle said first task;

causing the directory server to determine at least one server of the set of servers which is configured to handle said task, and to transmit specific information about said at least one server to said set of client computer; and

causing said client computer to transmit a task request to a preferred one of the servers chosen from said set of at least one server.

2. The method of claim 1 further comprising:

causing said client computer to start a countdown clock for a predetermined duration; and

causing, in response to said client computer receiving a response from said preferred one server indicating acceptance of the task request, said countdown clock to be disabled.

3. The method of claim 2 further comprising:

causing, in response to expiration of said predetermined duration said client computer to transmit information to said resource management service indicating failure of said preferred one server to respond to the task request; and

causing said directory server to remove said preferred server from said set of servers for said tasks.

4. The method of claim 2 further comprising:

causing, in response to expiration of said predetermined duration, said client computer to transmit information to said directory server indicating failure of said preferred one server to respond to the task request; and

causing said directory server to change the status of said preferred one server within said set to inactive for said tasks.

5. In a server system having a client computer, and a plurality of servers, at least one of the servers within said plurality being configured to operate a directory service, and at least two of the servers within said plurality being configured to operate resource management services which control overlapping subsets of tasks chosen from a master group of tasks, at least two of said servers within said plurality configured to perform overlapping subsets of tasks chosen from said master group of tasks, a method for controlling the assignment of tasks comprising:

determining that the client computer requires that a first task be performed by a server computer configured to handle that task;

causing the client computer to query a directory server to determine which of a set of servers within said plurality of servers is configured to handle said first task;

causing the queried directory server to determine at least one server of the set of servers that is configured to handle said task, and to transmit information about said set of at least one server to said client computer;

causing, in response to insufficient information for said client computer to choose a server capable of performing said first task, said client computer to transmit a request to at least one resource management service to cause said at least one resource management service to cause a first server chosen from the set to become configured to perform said first task; and

causing said client computer to transmit a request to said first server that said first task be performed.

6. The method of claim 5 further comprising

causing said client computer to start a countdown clock for a predetermined duration;

causing, in response to said client computer receiving a response from said first server indicating acceptance of the task request, said countdown clock to be disabled.

7. The method of claim 6 further comprising

causing, in response to expiration of said predetermined duration, said client computer to transmit information to said resource management service indicating failure of said first server to respond to said task request.

8. The method of claim 6 further comprising

causing, in response to expiration of said predetermined duration, said client computer to transmit information to said directory server indicating failure of said first server to respond to said task request.

9. The method of claim 6 further comprising:

transmitting information to said directory server in response to said predetermined duration having expired to indicate that said at least one server is not responding to the task request.

10. In a server system having a client computer, and a plurality of servers, at least one of the servers within said plurality being configured to operate a directory service and at least one of the servers within said plurality being configured to operate a resource management service and each of said servers within said plurality being configured to perform overlapping subsets of tasks within a master group of tasks, a method for performing the assignment of tasks comprising:

determining that the client computer requires that a task be performed by a server computer configured to handle that task;

causing the client computer to query the directory server to determine which servers within said plurality of servers is configured to handle said task;

causing the directory server to determine at least one server within said plurality of servers which is configured to handle said task, and to transmit specific information about said at least one server to said client computer;

causing said client computer to transmit a task request to a preferred one of said plurality of servers.

11. The method of claim 10 further comprising:

initiating a countdown clock for a predetermined duration;

disabling said countdown clock in response to said preferred one of said plurality of server having accepted the task request.

12. The method for performing assigned tasks in the server system of claim 11 in which at least one of the plurality of servers is configured to operate a resource management service, the method further comprising:

transmitting information to said resource management service in response to said predetermined duration having expired to indicate that said preferred server is not responding to task requests; and

causing said directory server to remove said preferred server from among said plurality of servers configured to perform the requested task.

13. The method of claim 11 further comprising:

causing said client computer to transmit information to said directory server in response to said predetermined duration having expired to indicate that said preferred server is not responding to the requested task; and

causing said directory server to change the status of said preferred server to inactive for performing the requested task.

14. In a server system having a client computer, and a plurality of servers, at least one of the servers within said plurality being configured to operate a directory service, and at least one of the servers within said plurality being configured to operate a resource management service which controls overlapping subsets of tasks chosen from a master group of tasks, at least two of said servers within said plurality configured to perform overlapping subsets of tasks chosen from said master group of tasks, a method for controlling the assignment of tasks comprising:

determining that the client computer, requires that a task be performed by a server computer configured to handle that task;

causing the client computer to query a directory server to determine which of said plurality of servers is configured to handle said first task;

causing the queried directory server to determine that at least one of the plurality of servers is configured to handle said task, and to transmit information about said at least one server to said client computer;

causing said client computer to transmit a request to at least one resource management service responsive to said information not being sufficient for said client computer to choose a server capable of performing said task for causing said at least one resource management service to configure one of said plurality of servers to perform said task; and

causing said client computer to transmit a request to said one of the plurality of servers to perform said task.

15. The method of claim 14 further comprising:

initiating a countdown clock for a predetermined duration; and

disabling the countdown clock in response to said at least one server having accepted the task request.

16. The method of claim 15 further comprising:

transmitting information to said resource management service in response to said predetermined duration having expired to indicate that said at least one server is not responding to the task request.