Copy Services

Copy Services features help you implement storage solutions to keep your business running 24 hours a day, 7 days a week by providing data duplication, data migration, and disaster recovery functions.

There are a number of advanced Copy Services functions that are supported across various environments such as IBM® i, System p and IBM Z , and servers from Sun and Hewlett-Packard.

The following Copy Services functions are available as optional features:
  • Point-in-time copy, which includes IBM FlashCopy® and FlashCopy SE
  • Remote mirror and copy, which includes the following functions:
    • Metro Mirror
    • Global Copy
    • Global Mirror
    • Metro/Global Mirror
    • Multiple Target PPRC
  • Remote mirror and copy for z/OS®, which includes IBM z/OS Global Mirror is available only for IBM Z environments.
  • Safeguarded Copy, which creates safeguarded backups that are not accessible by the host system
You can manage Copy Services functions by using any of the following methods:
  • IBM DS CLI (command-line interface)
  • IBM Copy Services Manager
  • Host I/O commands from IBM Z hosts
  • Failover and failback operations: In a planned or unplanned outage, such as a disaster, you can use failover and failback operations, which use Copy Services features to reduce the time that is required to synchronize remote mirror and copy volumes after switching between sites. (A failover operation is the process of switching production to a remote site. A failback operation is the process of returning production to its original location after a disaster.)
Note: The size limit for single volumes in a Copy Services relationship is 2 TB. This limit does not apply to extents (when part of multiple volumes).
Releasing space on CKD volumes that use thin provisioning
On an IBM Z® host, the DFSMSdss SPACEREL utility can release space from thin provisioned CKD volumes that are used by either Global Copy or Global Mirror.

For Global Copy, space is released on the primary and secondary copies. If the secondary copy is the primary copy of another Global Copy relationship, space is also released on secondary copies of that relationship.

For Global Mirror, space is released on the primary copy after a new consistency group is formed. Space is released on the secondary copy after the next consistency group is formed and a FlashCopy commit is performed. If the secondary copy is the primary copy of another Global Mirror relationship, space is also released on secondary copies of that relationship.