Specifications

xi
Compaq HSG80 Array Controller ACS Version 8.4 Configuration and CLI Reference Guide
Figures
The HSG80 Subsystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–3
HSG80 Array Controller Fibre Channel Optical Cabling . . . . . . . . . . . . . . . . . . . 1–8
Location of Controllers and Cache Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–10
HSG80 Controller Operator Control Panel (OCP) . . . . . . . . . . . . . . . . . . . . . . . . 1–11
Cache Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–16
Dual-battery ECB SBB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–17
Controller A and Controller B Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–2
This Controller and Other Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–3
Example of Host Port Shared IDs in Transparent Failover . . . . . . . . . . . . . . . . . . 2–6
Example of Separate Host Port IDs in Multiple-Bus Failover . . . . . . . . . . . . . . . . 2–8
Host Bus and Controller Device SCSI Bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–2
Containers and Storagesets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–4
PTL Naming Convention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–7
PTL Addressing in a Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–8
Locating Devices using PTLs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–9
Controller Port ID and Unit Numbers in Transparent Failover Mode . . . . . . . . . 3–11
Controller Port ID Numbers and Unit Numbers in Multiple-Bus
Failover Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–12
LUN Presentation Using Unit Offset on a Per-Host Basis . . . . . . . . . . . . . . . . . . 3–13
Placement of the Worldwide Name Label in a Subsystem . . . . . . . . . . . . . . . . . . 3–15
Units Created from Storagesets, Partitions, and Drives . . . . . . . . . . . . . . . . . . . . . 4–3
Striping Lets Several Disk Drives Participate in Each I/O Request . . . . . . . . . . . . 4–9
Distribute Members across Device Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–12
Mirrorsets Maintain Two Copies of the Same Data . . . . . . . . . . . . . . . . . . . . . . . 4–14
First Mirrorset Members on Different Buses . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–15
Parity Ensures Availability; Striping Provides Good Performance . . . . . . . . . . . 4–17
Striping and Mirroring in the Same Storageset . . . . . . . . . . . . . . . . . . . . . . . . . . 4–20