The system
provides Copy Services functions that can be used to improve availability and support disaster
recovery. Some system models can require a separate license
to use these functions. Verify your licensing requirement before using these
functions.
- IBM®
FlashCopy® function
- Makes an instant, point-in-time copy from a
source volume to a target volume.
- Metro Mirror
- Provides a consistent copy of a source volume on a target volume. Data is written to the target
volume synchronously after it is written to the source volume so that the copy is continuously
updated.
- Global Mirror
- Provides a consistent copy of a source volume on a target volume. The data is written to the
target volume asynchronously and the copy is continuously updated. However, the copy might not
contain the most recent updates when a disaster recovery operation is completed.
- Global Mirror with change volumes
- Enables support for Global Mirror
with higher recovery point objective (RPO) by the use of change volumes.
This
function is for use in environments where the available bandwidth between the sites is smaller than
the update rate of the replicated workload.
- IBM
HyperSwap® function
- Provides dual-site, active-active access to a volume. Data is written to the copies on both
sites synchronously so that both copies are continuously updated and can be used immediately if one
copy becomes unavailable.
Metro Mirror, Global Mirror, Global Mirror with
change volumes, and HyperSwap functions are types of
remote copy or remote replication.
If the system requires a remote mirroring license and it is configured correctly, the following
copy_type values can be specified in the CLI or management GUI to create remote
copy relationships:
- activeactive
- global
- metro