Cabling Channel A

Channel A loop cabling differences

The procedure for cabling the Channel A loops for a standard cluster and mirrored cluster are different. Follow the directions in the appropriate section:

Cabling the Channel A loops in a standard cluster
Cabling the Channel A loops in a mirrored cluster
Note
A switched cluster can be cabled as either a standard or mirrored cluster.

Cabling the Channel A loops in a standard cluster

To cable the Channel A loops in a standard cluster, complete the following steps, using the diagram for reference. The circled numbers in the diagram correspond to the step numbers in the table.

Step	Action
1	Cable the dual-port FC-AL adapter in slot 2, top port, to the disk shelf 1 Channel A LRC, ESH, ESH2, or AT-FCX Input port.
2	Cable the disk shelf 1 Channel A LRC, ESH, ESH2, or AT-FCX Output port to the disk shelf 2 Channel A LRC, ESH, ESH2, or AT-FCX Input port. Label this cable with a solid-colored label.
3	Repeat Step 2, connecting output to input, for the remaining disk shelves in the loop.
4	Set the terminate switches on the LRC or ESH modules to Off on all but the last disk shelf in the loop, then set the LRC or ESH terminate switches on the last disk shelf to On. Note The ESH2 is self-terminating and does not have a terminate switch. The AT-FCX is self-terminating as long as no cable is plugged into the Out port of the last shelf.
5	Repeat Step 1 through Step 4 for the partner node.
6	Go to Cabling Channel B.

Cabling the Channel A loops in a mirrored cluster

To cable the Channel A loops in a mirrored cluster, complete the following steps, using the diagram for reference.

Step	Action
1	Cable the dual-port FC-AL adapter in slot 8, top port, of the local node to the disk shelf 1 Channel A LRC, ESH, ESH2, or AT-FCX Input port of disk pool 1.
2	Cable the dual-port FC-AL in slot 5, top port, of the local node to the disk shelf 3 LRC, ESH, ESH2, or AT-FCX Input port of disk pool 0.
3	Cable the local disk shelf 1 Channel A LRC, ESH, ESH2, or AT-FCX Output port to the disk shelf 2 Channel A LRC, ESH, ESH2, or AT-FCX Input port for both disk pools. Label this cable with a solid-colored label.
4	Repeat Step 3, connecting Channel A output to input, for any remaining disk shelves in each disk pool. Note The illustration shows two disk shelves per disk pool. The number of disk shelves per pool might be different for your storage system.
5	Set the terminate switches on the LRC or ESH modules to Off on all but the last disk shelf in the disk pool, then set the LRC or ESH terminate switches on the last disk shelf to On. Note The ESH2 is self-terminating and does not have a terminate switch. The AT-FCX is self-terminating as long as no cable is plugged into the Out port of the last shelf.
6	Repeat Step 1 through Step 5 for the partner node.
7	Go to Cabling Channel B.