Method and system to provide highly available services

• US 20040019680A1
• Filed: 07/25/2002
• Published: 01/29/2004
• Est. Priority Date: 07/25/2002
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Chao, Ching-Yun, Liang, Chunlong
• Granted Patent: US 7,058,717 B2
• Time in Patent Office: Days
• US Class Current: 709/226
• CPC Class Codes: H04L 41/0893 Assignment of logical groups to network elements
• CPC Class Codes: H04L 41/0894 Policy-based network configuration management
• CPC Class Codes: H04L 41/0896 Bandwidth or capacity management, i.e. automatically increasing or decreasing capacities flow or congestion control using dynamic resource allocation, e.g. in-call renegotiation, H04L47/76
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/10015 Access to distributed or replicated servers, e.g. using brokers
• 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 67/1017 based on a round robin mechanism
• 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 67/306 User profiles
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

An example of a solution provided here comprises: providing a connection pool, said connection pool including a connection for each of a plurality of servers; applying a load-balancing policy to said connection pool; and assigning a connection from said connection pool to a client, according to said load-balancing policy. Another example of a solution comprises: providing a plurality of directory servers; providing a connection pool, said connection pool including a connection for each of said plurality of directory servers; applying a load-balancing policy to said connection pool; and assigning a connection from said connection pool to a client, according to said load-balancing policy. Methods for providing highly available services, systems for executing such methods, and instructions on a computer-usable medium, for executing such methods, are provided.

Claims

1. A method for providing highly available services, said method comprising:

providing a connection pool, said connection pool including a connection for each of a plurality of servers;

applying a load-balancing policy to said connection pool; and

assigning a connection from said connection pool to a client, according to said load-balancing policy.

2. The method of claim 1, further comprising:

continuously managing the content of said connection pool.

3. The method of claim 1, further comprising at least one action chosen from:

monitoring said connection pool for failures;

removing from said connection pool a connection to a failed server; and

adding a connection to said connection pool.

4. The method of claim 1, further comprising:

(a) trying to connect to at least one of said plurality of servers that was previously down;

(b) checking the availability of at least one of said plurality of servers that was previously up;

(c) waiting for a defined interval; and

(d) repeating (a)-(c) above.

5. The method of claim 1, further comprising:

detecting a failed operation;

changing the status of the server that corresponds to the assigned connection; and

assigning another connection from said connection pool to said client.

6. The method of claim 1, wherein said applying a load-balancing policy further comprises:

allowing a “

read”

operation on any of said plurality of servers; and

allowing a “

write”

operation on at least one of said plurality of servers, that is designated for “

read” and

“

write”

operations.

7. A method for providing highly available services, said method comprising:

providing a plurality of directory servers;

providing a connection pool, said connection pool including a connection for each of said plurality of directory servers;

applying a load-balancing policy to said connection pool; and

assigning a connection from said connection pool to a client, according to said load-balancing policy.

8. The method of claim 7, further comprising:

continuously managing the content of said connection pool.

9. The method of claim 7, further comprising at least one action chosen from:

monitoring said connection pool for failures;

removing from said connection pool a connection to a failed directory server; and

adding a good connection to said connection pool, when a directory server becomes available.

10. The method of claim 7, further comprising:

(a) trying to connect to at least one of said plurality of directory servers that was previously down;

(b) checking the availability of at least one of said plurality of directory servers that was previously up;

(c) waiting for a defined interval; and

(d) repeating (a)-(c) above.

11. The method of claim 7, further comprising:

detecting a failed operation;

changing the status of the directory server that corresponds to the assigned connection; and

assigning another connection from said connection pool to said client.

12. The method of claim 7, wherein said providing a connection pool further comprises utilizing JNDI.

13. The method of claim 7, wherein said plurality of directory servers includes a plurality of directory servers utilizing LDAP.

14. The method of claim 7, wherein:

said plurality of directory servers includes;

at least one directory server for “

read” and

“

write”

operations; and

at least one directory server for “

read”

operations; and

said applying a load-balancing policy further comprises;

allowing a “

write”

operation on said at least one directory server for “

read” and

“

write”

operations; and

allowing a “

read”

operation on any of said plurality of directory servers.

15. A system for providing highly available services, said system comprising:

means for providing a connection pool, said connection pool including a connection for each of a plurality of servers;

means for applying a load-balancing policy to said connection pool; and

means for assigning a connection from said connection pool to a client, according to said load-balancing policy.

16. The system of claim 15, further comprising:

means for continuously managing the content of said connection pool.

17. The system of claim 15, further comprising means for performing at least one action chosen from:

monitoring said connection pool for failures;

removing from said connection pool a connection to a failed server; and

adding a connection to said connection pool.

18. The system of claim 15, further comprising means for performing (a)-(d) below:

(a) trying to connect to at least one of said plurality of servers that was previously down;

(b) checking the availability of at least one of said plurality of servers that was previously up;

(c) waiting for a defined interval; and

(d) repeating (a)-(c) above.

19. The system of claim 15, further comprising:

means for detecting a failed operation;

means for changing the status of the server that corresponds to the assigned connection; and

means for assigning another connection from said connection pool to said client.

20. The system of claim 15, wherein said means for applying a load-balancing policy further comprises:

means for allowing a “

read”

operation on any of said plurality of servers; and

means for allowing a “

write”

operation on at least one of said plurality of servers, that is designated for “

read” and

“

write”

operations.

21. A computer-usable medium having computer-executable instructions for providing highly available services, said computer-executable instructions comprising:

means for providing a connection pool, said connection pool including a connection for each of a plurality of servers;

means for applying a load-balancing policy to said connection pool; and

means for assigning a connection from said connection pool to a client, according to said load-balancing policy.

22. The computer-usable medium of claim 21, further comprising:

means for continuously managing the content of said connection pool.

23. The computer-usable medium of claim 21, further comprising means for performing at least one action chosen from:

monitoring said connection pool for failures;

removing from said connection pool a connection to a failed server; and

adding a connection to said connection pool.

24. The computer-usable medium of claim 21, further comprising means for performing (a)-(d) below:

(a) trying to connect to at least one of said plurality of servers that was previously down;

(b) checking the availability of at least one of said plurality of servers that was previously up;

(c) waiting for a defined interval; and

(d) repeating (a)-(c) above.

25. The computer-usable medium of claim 21, further comprising:

means for detecting a failed operation;

means for changing the status of the server that corresponds to the assigned connection; and

means for assigning another connection from said connection pool to said client.

26. The computer-usable medium of claim 21, wherein said means for applying a load-balancing policy further comprises:

means for allowing a “

read”

operation on any of said plurality of servers; and

means for allowing a “

write”

operation on at least one of said plurality of servers, that is designated for “

read” and

“

write”

operations.