Dell EMC Solutions Enabler 9.2 SRDF Family CLI User Guide

Introduction to SRDF

The Dell EMC Symmetrix^® Remote Data Facility (SRDF^®) family of products offers a range of array based disaster recovery, parallel processing, high availability, and data migration solutions for VMAX^® Family and VMAX All Flash systems, including:

• HYPERMAX OS for VMAX3 Family 100K, 200K, 400K arrays, VMAX All Flash 250F, 450F, 850F, 950F arrays
• Enginuity 5876 for VMAX 10K, 20K, and 40K arrays

SRDF replicates data between 2, 3 or 4 arrays located in the same room, on the same campus, or thousands of kilometers apart. Replicated volumes may include a single device, all devices on a system, or thousands of volumes across multiple systems.

HYPERMAX OS 5977.691.684 introduces an additional SRDF configuration; SRDF/Metro.

The following image shows two-site SRDF configurations, one traditional and one SRDF/Metro.

In traditional SRDF configurations:

• A host at the production site is connected to the local array.
• SRDF device pairs are designated as the R1 side (local to the host) and R2 side (remote)
• R1 and R2 device pairs are connected over SRDF links.
• The production host writes I/O to the R1 side of the device pair at the primary site.
• SRDF mirrors the production I/O to the R2 side of the device pair at the secondary site(s).

In SRDF/Metro configurations:

• R2 devices acquire the personality (geometry, device WWN) of the R1 device .
• R1 and R2 devices to appear to hosts(s) as a single virtual device across the two SRDF paired arrays
• The host (multiple hosts in clustered configurations) can read and write to both the R1 and R2 devices.
• For single host configurations, host I/Os are issued by a single host. Multi-pathing software directs parallel reads and writes to each array.
• For clustered host configurations, host I/Os can be issued by multiple hosts accessing both sides of the SRDF device pair.