Exp3500 Attachment; Redundant Drive Channels - IBM System Storage DS3500 Introduction And Implementation Manual

7914Cabling2-1908.fm
You must use either a Category 5e or a Category 6 Ethernet cable when you are connecting a
DS3500 controller iSCSI host port to a gigabit Ethernet switch, and then connect a similar
Ethernet cable from the switch to the host iSCSI initiator port.

4.6 EXP3500 attachment

In this section we describe the requirements and best practise guidelines for connecting
EXP3500 enclosures to a DS3500 storage subsystem.
The DS3500 supports attachment of up to 96 drives. The DS3512 and EXP3512 enclosures
supports 12 drives and the DS3524 and EXP3524 enclosures supports 24 drives. The
DS3500 storage subsystem supports intermixing of EXP3512 and EXP3524 enclosures so
long as the total number of disk drives in the storage configuration does not exceed 96.
Table 4-1 shows the various combinations of DS3500 storage subsystem and EXP3500
enclosures that can be configured so that you do not exceed the limit of 96 drives.
Table 4-1 DS3500 storage subsystem and EXP3500 enclosures limits
DS3512
Enclosure Type
EXP3512
EXP3524
or
EXP3512
EXP3524
or
EXP3512
EXP3524
or
EXP3512
EXP3524

4.6.1 Redundant drive channels

Each DS3500 controller has a drive expansion channel with one x4 SAS port. The EXP3500
expansion enclosures that are connected to this port form one drive channel. Each drive
channel supports a maximum of 96 disk drives. In a dual-controller DS3500, one drive
channel from each controller combine to form a redundant drive-channel pair. If any
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IBM System Storage DS3500: Introduction and Implementation Guide
Draft Document for Review March 28, 2011 12:24 pm
DS3524
Enclosure quantity Enclosure type
7 EXP3512
0 EXP3524
or
5 EXP3512
1 EXP3524
or
3 EXP3512
2 EXP3524
or
1 EXP3512
3 EXP3524
Enclosure quantity
6
0
4
1
2
2
0
3