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Symmetrix Remote Data Facility (SRDF) solutions provide disaster recovery and data mobility solutions for Dell PowerMax, VMAX, VMAX3, and VMAX All Flash arrays. SRDF services are provided by the following operating environments:
SRDF replicates data between 2, 3, or 4 arrays located in the same room, on the same campus, or thousands of kilometers apart.
HYPERMAX OS 5977.691.684 and Solutions Enabler/Unisphere for VMAX 8.1 introduced support for SRDF/Metro for VMAX3 and VMAX All Flash families of storage arrays. SRDF/Metro significantly changes the traditional behavior of SRDF to better support your critical applications in high availability environments.
With SRDF/Metro, the SRDF secondary device is read/write accessible to the host and takes on the external identity of the primary device (geometry, device WWN, and so on). By providing this external identity on the secondary device, both the primary and secondary devices may then appear as a single virtual device across the two SRDF paired arrays for presentation to a single host or host cluster.
With both devices being accessible, the host or hosts (in the case of a cluster) can read and write to both primary and secondary devices with SRDF/Metro ensuring that each copy remains current, consistent, and addressing any write conflicts which may occur between the paired SRDF devices. A single PowerMax, VMAX3, or VMAX All Flash Array may simultaneously support multiple SRDF groups configured for SRDF/Metro operations and multiple SRDF groups configured for non-SRDF/Metro operations.
The following features were introduced with the PowerMaxOS 5978 Q3 2020 Service Release (SR) and Solutions Enabler/Unisphere for PowerMax 9.2:
This release also added support for the 4 port 25 GbE SLiC and protocol driver for all SRDF replication and host connectivity (RE/SE). This hardware expands PowerMax support for next generation Ethernet-based SAN fabrics, continuing to provide maximum I/O performance and fabric capabilities to the platform.
PowerMaxOS 5978 Q2 2019 Service Release and Solutions Enabler/Unisphere for PowerMax 9.1 introduced support for SRDF/Metro Online Device Expansion (ODE) and a new Unisphere interface for add/remove of SRDF/Metro devices based on the existing Storage Group add/remove device workflow. With Unisphere for PowerMax and Solutions Enabler 9.1 forward, we expanded our ODE support to include devices taking part in SRDF/Metro (Active) sessions; this new functionality is based on modifications to our existing Geometry Compatibility Mode (GCM) functionality for host visibility of devices. Unisphere 9.1 also provides new ease-of-use functionality by automating the addition of devices to a storage group which then adds corresponding SRDF paired devices for single hop, concurrent, and cascaded SRDF configurations.