Dell PowerVault ME4 Series Storage System Deployment Guide

Connecting the enclosure to hosts

A host identifies an external port to which the storage system is attached. The external port may be a port in an I/O adapter (such as an FC HBA) in a server. Cable connections vary depending on configuration. This section describes host interface protocols supported by ME4 Series controller enclosures and shows some common cabling configurations. ME4 Series controllers use Unified LUN Presentation (ULP), which enables a host to access mapped volumes through any controller host port.

ULP can show all LUNs through all host ports on both controllers, and the interconnect information is managed by the controller firmware. ULP appears to the host as an active-active storage system, allowing the host to select any available path to access the LUN, regardless of disk group ownership.