Dell PowerVault ME5 Series Storage System Deployment Guide

• When connecting SAS cables to IOMs, use only supported HD mini-SAS x4 cables.
• Use qualified HD mini-SAS to HD mini-SAS 0.5 m (1.64 ft) cables to connect cascaded enclosures in the rack.
• The maximum enclosure cable length that is allowed in any configuration is 2 m (6.56 ft).
• Using more than two expansion enclosures may require additional cables depending upon the number of enclosures and the cabling method used.
• Reverse-cabling for a fault-tolerant configuration may require additional or longer cables.

In the following cabling diagrams, the controller enclosure is shown at the top of the stack of connected expansion enclosures. You can invert the order of the stack for optimal weight and placement stability in the rack. The schematic representation of cabling remains unchanged. See Mount the enclosures in the rack for more detail.

When connecting multiple expansion enclosures to an expansion enclosure, use reverse cabling to ensure the highest level of fault tolerance.

The ME5 Series identifies controller modules and IOMs by enclosure ID and IOM ID.

The following figure shows the cabling configuration for a 2U controller enclosure with 2U expansion enclosures. The controller modules are identified as 0A and 0B, the IOMs in the first expansion enclosure are identified as 1A and 1B, and so on. Controller module 0A is connected to IOM 1A, with a chain of connections cascading down (blue). Controller module 0B is connected to the lower IOM (9B), of the last expansion enclosure, with connections moving in the opposite direction (green). Reverse cabling enables any expansion enclosure to fail—or be removed—while maintaining access to other enclosures.

The following figure shows the cabling configuration for a 5U84 controller enclosure with 5U84 expansion enclosures. The controller modules are identified as 0A and 0B, the IOMs in the first expansion enclosure are identified as 1A and 1B, and so on. Controller module 0A is connected to IOM 1A, with a chain of connections cascading down (blue). Controller module 0B is connected to the lower IOM (3B), of the last expansion enclosure, with connections moving in the opposite direction (green). Reverse cabling enables any expansion enclosure to fail—or be removed—while maintaining access to other enclosures.

Label the back-end cables

Label the back-end SAS cables that connect the controller enclosure and the expansion enclosures.