3. Connection from the P822 controller to port 1 of I/O module B on the bottom D2600 in Group 1
4. P822 controller
5. Connection from the P822 controller to port 1 of I/O module B on the bottom D2600 in Group 2
6. Connection from the P822 controller to port 2 of I/O module A on the top D2600 in Group 2
7. SAS daisy chain – port 1 of I/O module B on the top D2600 connects to port 2 of I/O module B on the
bottom D2600 and port 1 of I/O module A on the top D2600 connects to port 2 of I/O module A on the
bottom D2600
8. Connection from the P822 controller to port 2 of I/O module A on the top D2600 in Group 1
The following diagram illustrates the best performance. The difference between this cabling and fault
tolerance cabling is that the beginning and ending connections from the controller to a disk enclosure are
always to the first disk enclosure in the group. Essentially, the request from the controller to a disk
enclosure moves faster because it does not have to travel through a series of disk enclosures. However,
this cabling does not provide fault tolerance. If an I/O module in the first disk enclosure fails, you will lose
access to all disk enclosures in the group.
Setup and install
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