I/O Subsystem Positions, Fully Populated Rack (Rear View with IBFs)
C1 Rack
C2 I/O Book (Book 0)
1 First I/O Subsystem
2 Second I/O Subsystem
3 Third I/O Subsystem
4B Two IBFs (primary rack), Position 4
Appendix G. Subsystem Positioning and Cabling
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