FlashCopy
FlashCopy® replication creates a point-in-time copy in which the target volume contains a copy of the data that was on the source volume when the FlashCopy was established.
The DS8000® provides multiple logical subsystems (LSSs) within a single physical subsystem, while the following platforms provide multiple I/O groups:
- Systems running IBM Spectrum® Virtualize
All platforms can use local replication in which the source volume is located in one LSS or I/O group and the target volume is located in the same or another LSS or I/O group. Using the FlashCopy feature, you can reference and update the source volume and target volume independently.
Figure 1 illustrates a FlashCopy session.
TVT Instructions: This graphic was updated for Copy Services Manager 6.2.1, frg_i_flashcopy_v2.jpg. To capture this graphic from the Copy Services Manager GUI, click Sessions in the navigation tree > Click Create Session > In the Create Session window, select any storage systems other than XIV in the Choose Hardware Type list > In the Choose Session Type list, select FlashCopy.
- z/OS Management option
- When a z/OS system or sysplex name is set, the Flash command is submitted through the z/OS
connection to that system or sysplex to provide performance improvements during the FlashCopy
process for mainframe volumes.Note: To enable this feature and take advantage of the performance enhancements, volumes in the session must be attached to the system or sysplex and IOS APAR OA59561 must be applied. In addition, for all storage systems that are going to be managed, a z/OS connection must be defined on the Storage Systems panel. Ensure that you create a z/OS storage system connection (Storage connections) for each storage system in the system or sysplex that will be managed by the session.
Example
Jane works for a bank. Jane uses a FlashCopy session to make a point-in-time copy of the customer data in existing international accounts. Every night, the bank's servers start batch processing. Jane uses the FlashCopy session to create checkpoint restarts for the batch processing if the batch processing fails. In the batch processing, the first step is to balance all international accounts and to make a FlashCopy point-in-time copy of the resulting data. The second step in the batch processing is to complete the international disbursements.
If the second step in the batch process fails, Jane can use the data from the FlashCopy session that was taken of the first step to repeat the second step. In this way, Jane does not have to begin the entire process again. Jane also uses a CLI script that performs a FlashCopy operation every night at 11:59 PM, and another script that quiesces the database. She backs up the data to tape on the target storage system, and then sends the tape to the bank's data facility for storage.