Specifications

Escala Tower PL & S, E, T System Hardware
Chapter 3: External Storage and SAN Subsystems 23/116
9es3s1c3.doc
Rev 5.9
02/12/2003
2.1.5.4. Architecture: SP, LCC, disks, memory
The figure below summarizes the hardware architecture of a DPE enclosure. A DPE contains at least
one SP and one LCC. The hardware to implement the second FC-AL loop is optional. Individual
hardware components are discussed later in this document.
Mirrored
Write
Data
Standb
y
Power
S
y
stem A
SP A
RAID
en
g
ine
Hub
SP B
Hub
Standb
y
Power
S
y
stem B
AC Branch
A
AC Branch
B
Mutual
surve
y
Dual-ported Drives
To Hosts
Power
Suppl
y
A
Power
Suppl
y
B
Redundant
Processor
Fan
Module
Redundant
Disk
Fan
Module
LCC
Fibre Channel
Circuitry 1
cache cache
RAID
en
g
ine
LCC
Fibre Channel
Circuitry 1
The DPE components include:
•
One or two SPs (Storage Processors)
•
One or two LCCs (Link Controller Cards, shown as “fibre channel circuitry” in the figure above)
to implement one or two FC-AL loops
•
Up to 10 fibre channel dual ported disk modules
•
One or two power supplies each with its own power cord
•
One redundant fan module to cool the disks and another to cool the SPs
•
To implement write caching, one or two SPSs (Standby Power Supplies – also called BBUs, i.e.
Battery Backup Units).
2.1.5.4.1. SPs (Storage Processors) and host interface
The SP provides the following features to the disk subsystem:
•
RAID processing
•
host interface management
•
backend management
•
memory
•
built-in hub for external connection.