enclosure type and model in every storage subsystem configuration. In addition,
not all controller firmware levels support all available storage enclosures or storage
subsystems.
In general, if a storage subsystem supports multiple storage enclosures with
different model numbers and machine types, you can connect the storage
enclosures to the storage subsystem on the same redundant drive loop/channel by
using the cabling rules that are described in the storage subsystem documentation.
As a best practice, group the storage enclosures by model and machine type when
you connect cables in the same redundant drive loop/channels. However, because
of storage enclosure architecture differences, there might be certain restrictions
when you connect some combinations of storage enclosures in the same drive
loop/channel.
Table 6. Storage enclosure compatibility with storage subsystems by model for DCS Series storage subsystems
Storage subsystem
DCS3700 Expansion Enclosure
EXP3800
DCS3700 with Gen2 Controllers
U
DCS3860 with Gen2 Controllers
U
U
Table 7. DCS3700 and EXP3800 expansion enclosures supported by controller firmware levels
Firmware level
DCS3700 Expansion
Enclosure
EXP3800
07.84.xx.xx
Yes
No
07.86.xx.xx or later
Yes
Yes
Important:
To avoid unpredictable results, do not change the speed of a drive loop
while the storage subsystem is turned on. Also, the storage enclosures must be
power cycled for the new speed setting to be recognized correctly.
To change the speed of a drive loop, complete the following steps:
1.
Prepare applications for storage subsystem shutdown.
2.
Shut down the storage subsystem.
3.
Shut down the storage enclosures.
4.
Change the storage enclosure speed settings.
5.
Turn on the power to the storage enclosures.
6.
Turn on the power to the storage subsystem.
7.
Restore storage subsystem host application operations.
Note:
For more information about turning on a storage subsystem and turning it
off, see the documentation that comes with your storage subsystem. For more
information, see http://www.ibm.com/systems/support/storage/disk/.
12
IBM System Storage DCS Series with Gen2 controllers Hard Disk Drive and Storage Enclosure Installation and Migration
Guide
Summary of Contents for System Storage DCS Series
Page 89: ......