Intermixing The Exp810 And Exp710 In The Same Drive Channel; Controllers - IBM DS4800 User, Installation And Maintenance Manual

Notes:
1. Important: DS4000 EXP700s are not supported by the DS4800 unless they
2. The DS4800 does not support the attachment of storage expansion enclosures

Intermixing the EXP810 and EXP710 in the same drive channel

You can intermix the EXP810 and EXP710 in the same drive channel, but the Link
Rate switch for all storage expansion enclosures in the intermixed drive channel
must be set to 2 Gbps.
There are maximum limits to the number of fibre channel hard drives that you can
configure in redundant drive channel pairs. The maximum number of drives dictates
a fixed number of supported EXP710 and EXP810 drive enclosure combinations.
Table 4 lists the numbers of EXP710 and EXP810 storage expansion enclosures
that you can combine for use in a single redundant drive channel/loop pair. Table 4
assumes that a DS4000 storage subsystem is generally capable of addressing the
maximum of 112 fibre channel hard drives for each redundant drive channel pair.

Controllers

The DS4800 has two RAID controllers. Both controllers are identical and
interchangeable. The controllers install from the rear of the storage subsystem. The
10
IBM System Storage DS4800 Storage Subsystem: Installation, User's, and Maintenance Guide
Table 3. Maximum number of storage expansion enclosures (continued)
Enclosure type
EXP710 and EXP810
1
The intermix of EXP100 and EXP810 storage expansion enclosures behind a DS4800
subsystem is not currently supported. Please contact IBM reseller and representatives for
such support in the future.
2
The value 15 assumed that one of the redundant DS4800 drive channel pairs must have
only EXP710 enclosures attached.
have been upgraded (with the DS4000 EXP700 Models 1RU/1RX
Switched-ESM Option Upgrade Kit) to have the same internal switched
capabilities as the DS4000 EXP710.
operating at 1 Gbps, such as the EXP500.
Table 4. Supported EXP810 and EXP710 enclosure combinations per redundant drive
channel pair
Number of Number of
EXP810s EXP710s
0 8
1 6
2 5
3 4
4 3
5 2
6 1
7 0
Maximum number of
enclosures in a redundant
DS4800 drive channel pair
1
7
Total number Total number
of drives in of drives in
EXP810s EXP710s
0 112
16 84
32 70
48 56
64 42
80 28
96 14
112 0
Maximum number of
enclosures in a DS4800
subsystem
2
14 (or 15)
Total number of drives
in a mixed EXP710 and
EXP810 drive channel
= 112
= 100
= 102
= 104
= 106
= 108
= 110
= 112