IBM DS4800 - Page 82

second port of the dual-ported drive channel. For example, in drive channel/loop
pair 1, both ports 4 and 3 of channel 1 and port 1 and 2 of channel 3 are used.
Note: In the following drive cabling figures, the DS4800 graphics are simplified to
show only the drive ports of each controller.
60 IBM System Storage DS4800 Storage Subsystem: Installation, User’s, and Maintenance Guide