[54] APPARATUS FOR SYNCHRONIZING
OPERATOR INITIATED COMMANDS WITH
A FAILOVER PROCESS IN A DISTRIBUTED
PROCESSING SYSTEM
[75] Inventors: Robert F. Bartfai, West Shokan; John
Divirgilio, Middletown; John W.
Doxtader, Hurley; Peter J. LeVangia,
Kingston; Laura J. Merritt,
Wappingers Falls; Nicholas P. Rash,
Poughkeepsie; Kevin J. Reilly,
Kingston, all of N.Y.
[73] Assignee: International Business Machines Corporation, Armonk, N.Y.
[ * ] Notice: This patent is subject to a terminal disclaimer.
[21] Appl. No.: 08/827,133 [22] Filed: Mar. 27, 1997
[51] Int. CI.7 G06F 11/00; G06F 11/22
[52] U.S. CI 714/4; 714/12; 709/248;
709/400; 710/61
[58] Field of Search 395/182.02, 182.05,
395/182.09, 182.1, 182.11, 182.13, 182.21, 183.17, 200.78, 553, 561, 595, 670, 671, 672, 881; 371/5.4, 47.1; 340/825.14; 714/4, 7, 11, 12, 13; 709/248, 400; 710/61
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OTHER PUBLICATIONS
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"Supervisor Recovery in Ring Networks", A. Goyal and R. Nelson, IBM Technical Disclosure Bulletin, vol. 27, No. 8, Jan. 1865, pp. 4715-4717.
Primary Examiner—Dieu-Minh T. Le
Attorney, Agent, or Firm—Floyd A. Gonzalez; David A.
Fox; Cantor Colburn LLP
[57] ABSTRACT
An apparatus for synchronizing operator commands with a failover process in a distributed system having a control workstation and a plurality of nodes. One of the nodes of the distributed system is designated a primary node and one of the nodes is designated a backup node. The backup node includes a backup daemon for performing a failover process if the primary node fails such that the backup node becomes the primary node. Shell scripts send a command string to be synchronized with the operation of the backup daemon from the control workstation to the backup node. The backup daemon is then checked to determine if the backup daemon is sleeping, and, in the event the backup daemon is sleeping, commands derived from the command string are enqueued in a work queue for processing by the backup daemon. The backup daemon is then awakened such that the derived commands in the work queue are processed. In the event that the backup daemon is busy, commands derived from the command string are failed, thereby synchronizing the derived commands with the processing of the backup daemon.
12 Claims, 4 Drawing Sheets
