HSG80 ACS Solution Software V8.6 for SGI IRIX Installation and Configuration Guide

Preparing the Host System 3–9
Arbitrated Loop Device Name Convention
SGI Irix creates unique device names for devices attached to the Arbitrated Loop Fibre
Channel host adapters on the system. Understanding the device nomenclature will help in
providing device name-related answers in the following section.
Format used for LUN 0: dksxdysa
Format used for other LUNs: dksxdylzsa
NOTE: The “l” in the example is the letter “el”)
x = controller (host Fibre Channel adapter) number assigned by host.
y = Loop ID in decimal
z = Logical Unit Number, LUN
a = Slice or partition number
The fourth slice (partition) on RAID Array logical unit D4 on Fibre Channel controller 10
wouldbeseenas:
dks10d64l4s3
Fabric Device Name Convention
SGI Irix creates unique device names for devices attached to the Fabric Fibre Channel host
adapters on the system. Understanding the device nomenclature will help in providing
device name-related answers in the following section.
Format used for LUNs: /dev/rdsk/<nodeWWN>/lunzvol/cxp<portID>
NOTE: The “l” in the example is the letter “el”)
z (in lunzvol) = Logical Unit Number, LUN
x (in cxp<portID>) = controller (host Fibre Channel adapter) number assigned by host.
<nodeWWN> = worldwide name (Node ID) of HSG80 controllers (THIS and OTHER)
<portID> = Port ID of the HSG80 controller (THIS or OTHER)
Creating the Disk Label
The disk label contains a variety of information about the storage device. Included in the
label are settings for a performance enhancement feature called Command Tagged
Queuing (CTQ). In order to utilize CTQ, it must be enabled in the disk label for each
RAID Array logical unit that is visible to the host. In the following example, CTQ is
enabled and the queue depth is set.