Home > Storage > PowerMax and VMAX > Data Protection > Dell PowerMax and VMAX All Flash: SRDF/Metro Overview and Best Practices > Createpair operation
An SRDF createpair operation, with an appropriate SRDF/Metro option specified, places the new SRDF device pairs into an SRDF/Metro configuration. The user may perform the createpair operation to add devices into the SRDF group as long as the new SRDF devices created are not ready (NR) on the SRDF link with a suspended or partitioned state.
The SRDF device pairs may be made read/write (RW) on the SRDF link as a part of the createpair operation by specifying either establish or restore option. The createpair operation creates the SRDF device pairs and makes them read/write on the SRDF link. Alternately, the user may perform a createpair operation followed by an establish or restore operation to begin the device synchronization process between newly created device pairs. In either case, the resulting SRDF mode of operation will be Active for these devices to reflect an SRDF/Metro configuration.