Facilitating synchronization of servers in a coordinated timing network

• US 7,779,109 B2
• Filed: 10/22/2007
• Issued: 08/17/2010
• Est. Priority Date: 01/31/2007
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Hack, Michel H. T., Dahlen, Dennis J., Crabtree, Donald, Sevigny, Denise M., Carlson, Scott M., Dhondy, Noshir R., Smith, Ronald M. Sr., Wierbowski, Judith A., Whitney, David E., Elko, David A.
• Primary Examiner(s): Jacobs; Lashonda T
• Application Number:
  US11/876,152
• Publication Number:
  US 20080183895A1
• Time in Patent Office: 1,030 Days
• Field of Search: 709/223, 709/224, 709/203, 709/219, 370/395.62
• US Class Current: 709/223
• CPC Class Codes: G06F 1/12 Synchronisation of different clock signals provided by a plurality of clock generators
• CPC Class Codes: G06F 1/14 Time supervision arrangements, e.g. real time clock
• CPC Class Codes: H04J 3/0641 Change of the master or reference, e.g. take-over or failure of the master
• CPC Class Codes: H04J 3/0661 using timestamps
• CPC Class Codes: H04L 69/28 Timers or timing mechanisms used in protocols

Abstract

A timing network is provided that includes a plurality of servers. The servers of the network obtain information used to maintain the servers in time synchronization, thus ensuring the integrity of the servers.

Claims

1. A computer program product for providing a coordinated timing network, the computer program product comprising:

a storage medium readable by a processor and storing instructions for execution by the processor for performing a method comprising;

obtaining, by a server of a timing network, timing clock information for the server, said server obtaining the timing clock information from a single primary active server of the timing network and not from an external clock source, said single primary active server being the primary reference time to the server and said single primary active server obtaining the timing clock information from an external time source;

obtaining by the server timing network data including configuration information of the timing network, primary reference time information, time zone information, and leap second change scheduling;

using by the server at least a portion of the timing network data and the timing clock information to ensure the server of the timing network is adhering to the configuration and is synchronized to a coordinated server time (CST) timing network specified synchronization threshold that meets high-speed computing requirements; and

recognizing by the server that it is out of synchronization and may not have valid configuration information, wherein the server that is out of synchronization is not a part of the timing network.

2. The computer program product of claim 1, wherein the server cannot operate for more than a prespecified amount of time without knowing the configuration information.

3. The computer program product of claim 1, wherein the configuration comprises the single primary active server, the server and one or more other servers, and wherein the obtaining the timing network data, the using and the recognizing are performed by each server of the one or more other servers.

4. The computer program product of claim 1, wherein the single primary active server and the server comprise the same timing network identifier.

5. The computer program product of claim 1, wherein the obtaining the timing network data is performed by passing information via messages using a Server Time Protocol message protocol.

6. The computer program product of claim 1, wherein the method further comprises:

obtaining by the single primary active server the primary reference time from an external time source; and

steering by the single active primary server its time-of-day clock to the primary reference time.

7. The computer program product of claim 1, wherein the single primary active server and the server are coupled via one or more low latency links.

8. The computer program product of claim 1, wherein the single primary active server is in network communications with the server via a Coordinated Timing Network configured to maintain time synchronization, the single primary active server sending Server Time Protocol messages by way of said Coordinated Timing Network.

9. The computer program product of claim 1, wherein the using by the server at least a portion of the timing network data and the timing clock information to ensure the server is adhering to the configuration comprises at least one of determining that its timing network identifier is the same as the timing network identifier of the single primary active server, and determining that configuration information obtained by the server is up-to-date information for the timing network.

10. The computer program product of claim 1, wherein the server has associated therewith a timing mode indicating whether the server is in local, external time reference (ETR) or server time protocol (STP) timing mode.

11. The computer program product of claim 1, wherein the server has associated therewith a timing state indicating whether the server is in a synchronized, unsynchronized or stopped state.

12. The computer program product of claim 1, wherein the server has associated therewith a clock source state indicating whether the server has a usable clock source.

13. A computer system for providing a coordinated timing network, the computer system comprising:

a memory; and

a processor in communications with the memory, wherein the computer system is capable of performing a method, said method comprising;

obtaining, by a server of a timing network, timing clock information for the server, said server obtaining the timing clock information from a single primary active server of the timing network and not from an external clock source, said single primary active server being the primary reference time to the server and said single primary active server obtaining the timing clock information from an external time source;

obtaining by the server timing network data including configuration information of the timing network, primary reference time information, time zone information, and leap second change scheduling;

using by the server at least a portion of the timing network data and the timing clock information to ensure the server of the timing network is adhering to the configuration and is synchronized to a coordinated server time (CST) timing network specified synchronization threshold that meets high-speed computing requirements; and

recognizing by the server that it is out of synchronization and may not have valid configuration information, wherein the server that is out of synchronization is not a part of the timing network.

14. The computer system of claim 13, wherein the server cannot operate for more than a prespecified amount of time without knowing the configuration information.

15. The computer system of claim 13, wherein the configuration comprises the single primary active server, the server and one or more other servers, and wherein the obtaining the timing network data, the using and the recognizing are performed by each server of the one or more other servers.

16. The computer system of claim 13, wherein the single primary active server and the server comprise the same timing network identifier.

17. The computer system of claim 13, wherein the single primary active server and the server are coupled via one or more low latency links.

18. The computer system of claim 13, wherein the single primary active server is in network communications with the server via a Coordinated Timing Network configured to maintain time synchronization, the single primary active server sending Server Time Protocol messages by way of said Coordinated Timing Network.

19. The computer system of claim 13, wherein the server has associated therewith a timing mode indicating whether the server is in local, external time reference (ETR) or server time protocol (STP) timing mode.

20. A method to provide a coordinated timing network, said method comprising:

obtaining, by a server of a timing network, timing clock information for the server, said server obtaining the timing clock information from a single primary active server of the timing network and not from an external clock source, said single primary active server being the primary reference time to the server and said single primary active server obtaining the timing clock information from an external time source;

obtaining by the server timing network data including configuration information of the timing network, primary reference time information, time zone information, and leap second change scheduling;

using by the server at least a portion of the timing network data and the timing clock information to ensure the server of the timing network is adhering to the configuration and is synchronized to a coordinated server time (CST) timing network specified synchronization threshold that meets high-speed computing requirements; and

recognizing by the server that it is out of synchronization and may not have valid configuration information, wherein the server that is out of synchronization is not a part of the timing network.

21. The method of claim 20, wherein the server cannot operate for more than a prespecified amount of time without knowing the configuration information.

22. The method of claim 20, wherein the configuration comprises the single primary active server, the server and one or more other servers, and wherein the obtaining the timing network data, the using and the recognizing are performed by each server of the one or more other servers.

23. The method of claim 20, wherein the single primary active server and the server comprise the same timing network identifier.

24. The method of claim 20, wherein the single primary active server is in network communications with the server via a Coordinated Timing Network configured to maintain time synchronization, the single primary active server sending Server Time Protocol messages by way of said Coordinated Timing Network.