Comparison of Copy Services features
The features of the Copy Services aid with planning for a disaster.
Table 1 provides a brief summary of the
characteristics of the Copy Services features that are available for the storage system.
| Feature | Description | Advantages | Considerations |
|---|---|---|---|
| Multiple Target PPRC | Synchronous and asynchronous replication | Mirrors data from a single primary site to two secondary sites simultaneously. | Disaster recovery scenarios depend on support from controlling software such as Geographically Dispersed Parallel Sysplex (GDPS®) and IBM Copy Services Manager |
| Metro/Global Mirror | Three-site, long distance disaster recovery replication | A backup site is maintained regardless of which one of the sites is lost. | Recovery point objective (RPO) might grow if bandwidth capability is exceeded. |
| Metro Mirror | Synchronous data copy at a distance | No data loss, rapid recovery time for distances up to 300 km. | Slight performance impact. |
| Global Copy | Continuous copy without data consistency | Nearly unlimited distance, suitable for data migration, only limited by network and channel extenders capabilities. | Copy is normally fuzzy but can be made consistent through synchronization. |
| Global Mirror | Asynchronous copy | Nearly unlimited distance, scalable, and low RPO. The RPO is the time needed to recover from a disaster; that is, the total system downtime. | RPO might grow when link bandwidth capability is exceeded. |