IBM NeXtScale System Planning And Implementation Manual page 31

A chassis that includes shared fans and cooling.
The n1200 Enclosure supplies the cooling and power to maximize energy
efficiency, but leaves management and connectivity to the compute nodes,
which minimizes cost.
Cables, connectors, and controls at the front.
With the exception of the power cords, all cabling is at the front of the chassis.
All controls and indicators also are at the front. This configuration makes
access, server swap-outs, and overall systems management easier.
Each compute node has a front connector for a local console for use if you
need crash-cart access. Also, each compute node has a pull-out tab at the
front for system and customer labeling needs, as shown in Figure 2-2.
KVM port
Pull out label tab
Figure 2-2 Front of the IBM NeXtScale nx360 M4
Because the cables do not clog up the back of the rack, air flow is improved
and thus energy efficiency also is improved. The harder the fans work to
move air through server, the more power they use.
Your support staff who work in the data center can tell you the front of the rack
is a much more enjoyable environment to spend time in because it might
easily be 30°F (16°C) cooler at the front than at the back. People cannot stay
in the rear of the rack that long before its no longer comfortable. Also, the front
of rack is less noisy than the rear of the rack because of fan noise.
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Chapter 2. Positioning