Drive Interface Ports; Host-Side Mini-Hub Interface Ports; Drive-Side Mini-Hub Interface Ports - IBM TotalStorage DS4400 User Manual

Host
mini-hub
ports
Figure 18. Host-side mini-hub interface ports

Drive interface ports

The DS4400 Storage Server comes with drive-side mini-hubs 1 and 2 installed.
Each drive mini-hub connects to Controller A and Controller B and represents a
single drive loop. The drive loops must be set up in pairs to support redundant drive
loop configurations (two data paths per storage expansion enclosure). DS4400
Storage Servers use only redundant drive-loop configurations. See Figure 19 for an
illustration of the drive-side mini-hub interface ports.
Figure 19. Drive-side mini-hub interface ports
The maximum number of storage expansion enclosures that can be connected per
pair of redundant drive loops depends on the IBM DS4000 storage expansion
enclosure models used. The following DS4000 storage expansion enclosure types
are supported by the DS4400 Storage Server:
v FAStT EXP500
v DS4000 EXP700
v DS4000 EXP710
v DS4000 EXP100
Host mini hubs
Controller A
1 2 3 4
2 Gb/s 2 Gb/s 2 Gb/s 2 Gb/s
1 Gb/s 1 Gb/s 1 Gb/s 1 Gb/s
! ! ! !
OUT OUT OUT OUT
IN IN IN IN
Drive C and D for
redundant loop 2
Drive A and B for
redundant loop 1
2 Gb/s 2 Gb/s 2 Gb/s 2 Gb/s
1 Gb/s 1 Gb/s 1 Gb/s 1 Gb/s
! ! ! !
OUT OUT OUT OUT
IN IN IN IN
Use one port on each
mini hub to connect
a drive loop cable
Controller B
Controller A
Controller B
2 Gb/s 2 Gb/s
1 Gb/s 1 Gb/s
! !
OUT OUT
IN IN
4 3 2 1
2 Gb/s 2 Gb/s 2 Gb/s 2 Gb/s
1 Gb/s 1 Gb/s 1 Gb/s 1 Gb/s
! ! ! !
OUT OUT OUT OUT
IN IN IN IN
Leave one port unoccupied
for future upgrades
2 Gb/s 2 Gb/s
1 Gb/s 1 Gb/s
! !
OUT OUT
IN IN
Drive
mini-hub
ports
Chapter 1. Introduction
15