Remote Copy configurations overview

1-to-1 configuration

A unidirectional 1-to-1 Remote Copy configuration consists of one storage system that is the primary system, and one storage system that is the backup storage system. The primary storage system holds only primary volume groups and the backup storage system holds only secondary volume groups.

A bidirectional 1-to-1 Remote Copy configuration consists of two storage systems that each function as both a primary and backup storage system. Each storage system contains both primary and secondary volume groups and provides backup for the other, according to the direction of replication specified for each volume group.

N-to-1 configuration

An N-to-1 Remote Copy configuration is composed of multiple Remote Copy pairs. A maximum of four primary storage systems can use the same backup storage system. The configuration can have up to four unidirectional or bidirectional Remote Copy pairs, as long as the remote target system has the minimum number of nodes required to support the number of source systems.

1-to-N configuration

A 1-to-N Remote Copy configuration is composed of multiple Remote Copy pairs. A single primary storage system can use a maximum of four backup storage systems. One primary system participates in four Remote Copy pairs, one for each backup system.

M-to-N configuration

An M-to-N Remote Copy configuration is comprised of 4x4 fan-in and fan-out with bidirectional data replication. The replication occurs without the need for dedicated Remote Copy pairs. Replication modes can be either synchronous, asynchronous periodic, or a mixture of modes.

IMPORTANT:
A storage system can be part of only one remote copy configuration. Thus to create a storage system linked pair using a storage system that is already a part of another linked pair, you have to:

  • Edit the existing Remote Copy configuration.

  • Then add the new storage system to the existing Remote Copy configuration.

  • Configure the Remote Copy links.

Synchronous long-distance configuration

A synchronous long distance (SLD) Remote Copy configuration is composed of two targets: one synchronous group and one asynchronous periodic group.

One primary system uses two backup systems and participates in two Remote Copy pairs, one for each backup system. The Remote Copy volume groups from the primary storage system are replicated to the two separate target storage systems simultaneously. Data is replicated to one target in synchronous mode and to the second in asynchronous periodic mode.