×

Method and means for making a dual volume level copy in a DASD storage subsystem subject to updating during the copy interval

  • US 5,875,479 A
  • Filed: 01/07/1997
  • Issued: 02/23/1999
  • Est. Priority Date: 01/07/1997
  • Status: Expired due to Term
First Claim
Patent Images

1. A method for duplexing volumes on an external subsystem of tracked cyclic storage devices subject to host-originated updating, a volume being a unit of storage including the elements of one or more datasets or the like and accessible to a counterpart one of the storage devices, said duplexing to be used with any host-based copy functions such as concurrent copy or extended remote copy or subsystem-based copy functions such as dual copy or peer-to-peer remote copy, comprising the steps of:

  • (a) forming a list structure defining copy status and copy order of the one or more data sets or descriptors in a first volume;

    (b) setting a first copy status value in the list structure to selected ones of the one or more datasets or descriptors in the first volume;

    (c) copying from the first to a second volume each of the one or more datasets or descriptors in the list structure having a copy status set to the first value in the defined copy order, and setting the copy status of each dataset or descriptor so copied to a second value; and

    (d) resetting the copy status in the list structure to the first value of any datasets or descriptors in the primary volume updated during the pendency of step (c) and already copied to the secondary volume; and

    repeating step (c) at least once.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×