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Table 17. Maximum number of drives per drive channel by enclosure type
Storage expansion
enclosure
Maximum number of drives
Number of storage
expansion enclosures
EXP5000
112
7 EXP5000
EXP5060
120
2 EXP5060
EXP5000 and EXP5060
108
1 EXP5060 and 3 EXP5000
In Figure 35, drive channel 1 of controller A and drive channel 5 of controller B
combine to form a DS5100 and DS5300 drive channel pair. If any component of
drive channel 1 fails, the RAID controllers can still access the storage expansion
enclosures in drive channel 1 through drive channel 5. Similarly, drive channel 2 of
controller A and drive channel 6 of controller B combine to form the second of the
two DS5100 and DS5300 drive channel pairs. If any component of drive channel 2
fails, the RAID controllers can still access the storage expansion enclosures in drive
channel 2 through drive channel 6.
Figure 35 shows the storage expansion enclosures in each drive channel pairs
connected to only one drive port in the two-ported drive channel. For example, in
drive channel pair 1, only port 8 of channel 1 and port 1 of channel 5 are used.
Note:
In the following drive cabling figure, the DS5100 and DS5300 graphic is
simplified to show only the drive ports of each controller. The storage
expansion enclosures are simplified to show only the ESM FC ports.
Non-trunking cabling
Non-trunking cabling is the cabling scheme where the controller drive ports are
connected to the EXP5000 or EXP5060 drive channel ports labeled 1B on both
ESMs of the EXP5000 or EXP5060 storage expansion enclosures, forming a pair of
redundant connections between the storage subsystem and the storage expansion
enclosure. This is the cabling that is supported when intermixing the EXP5060 and
EXP5000 or EXP810 storage expansion enclosures behind the same drive channel
or drive channel port.
ds50075
Left ESM
Left ESM
Left ESM
Right ESM
Right ESM
DS5000 Controller A
DS5000 Controller B
Redundant drive
channel pair 1
Figure 35. Example of redundant drive channel pairs
Chapter 3. Cabling the storage subsystem
61