About FC paths

Storage Subsystem Administration Guide for Hitachi NAS Platform

Part Number

The NAS server accesses the storage system through a minimum of two Fibre Channel (FC) paths (at least one from each of the FC switches). Unless otherwise stated, the recommended number of paths per SD should be limited to 16 (2 HNAS host FC ports per switch x 2 switches x 4 target ports per switch). An FC path is made up of the server’s host port ID, the storage system port WWN (worldwide name), and the SD identifier (ID).

The following illustration shows a complete path from the server to each of the SDs on the storage system:

FC interface

You can display information about the FC paths on the server/cluster through the command line interface (CLI), using the fc-host-port-load, fc-target-port-load, and the sdpath commands.

Fibre channel interface

The ports are in reverse order from prior gateways (due to mounting the HBA within the chassis):
  • Left to right: FC 4-3-2-1 (earlier generations were FC 1-2-3-4)
  • 2-node maximum for DAS storage (which is the same for prior gateways)
Figure. FC interface ports FC ports