Intermixing Exp810 And Exp710 - IBM Midrange System DS4000 Series Hardware Manual

Further information can be found at the following address:
http://www-03.ibm.com/servers/storage/disk/ds4000/exp810/
Figure 3-4 EXP810 front view
Note: There is also an EXP810 model designed to be powered from a - 48 V dc Telco
industry standard power source and it is NEBS-3 compliant. It includes an air filter option
with the optional front bezel.

3.3.3 Intermixing EXP810 and EXP710

When intermixing the EXP810 and EXP710, even though the enclosure grouping by type is
not a requirement, IBM recommends that you group them by enclosure type in a redundant
drive channel pair to simplify maintenance and troubleshooting. Also, the EXP810 link rate
switch must be set at 2 Gbps if you use them in the same dive channel.
There is a limit for the number of maximum configurable disks in redundant drive channel
pairs. This limit determines the fixed number of drive enclosure combinations (Table 3-1). The
total number of configurable drives is 112.
Table 3-1 Total number of attached expansion units
Enclosure
EXP710
EXP810
Intermixed
IBM does not recommend the intermixing of expansion units in the same redundant drive
channel pair. IBM recommends connecting all of the EXP710s to a redundant drive channel
pair and all of the EXP810s to the other (second) redundant drive channel pair. In this case,
you can operate the EXP810 at a higher speed and avoid the subsequent separation of
intermixed drive channel pairs.
For detailed instructions for any intermix configuration, see the IBM System Storage
DS4000/DS5000 Hard Drive and Storage Expansion Enclosure Installation and Migration
Guide, GC53-1139.
IBM System Storage DS4000 and Storage Manager V10.30, SG24-7010 also has information
about intermixing different expansion enclosures behind the DS4000 storage systems.
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IBM Midrange System Storage Hardware Guide
Maximum number of configurable expansion units in
a drive channel pair
8
7
7