IBM 9008-22L, Site And Hardware Planning

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1. Power cables
2. Communications (serial attached SCSI, InfiniBand, remote input/output, and peripheral component
interconnect express) cables
Note: Install and route the communications cables, starting with the smallest diameter first and
then progressing to the largest diameter. This applies to installing them into the cable management
arm and retaining them to the rack, brackets, and other features that might be provided for cable
management.
• Install and route the communications cables, starting with smallest diameter first and then progressing
to the largest diameter.
• Use the innermost cable-management bridge lances for power cables.
• Use the middle cable-management bridge lances for communications cables.
• The outermost row of cable-management bridge lances is available for use when routing cables.
• Use the cable raceways on the sides of the rack to manage excess power cables.
• Four cable-management bridge lances are on the top of the rack. Use these bridge lances to route the
cables from one side of the rack to the other, by routing to the top of the rack, where possible. This
routing helps to avoid having a cable bundle that blocks the cable exit opening at the bottom of the
rack.
• Use the cable management brackets that are provided with the system to maintain concurrent
maintenance routing.
• Maintain a minimum bend diameter of 101.6 mm (4 in.) for communications (SAS, IB, and PCIe) cables.
• Maintain a minimum bend diameter of 50.8 mm (2 in.) for power cables.
• Use the shortest-length cable available for each point-to-point connection.
• If cables must be routed across the rear of a drawer, leave enough slack to reduce the tension on the
cables for maintenance of the drawer.
• When routing cables, leave enough slack around the power connection on the power distribution unit
(PDU) so that the wall-to-PDU power cord can be attached to the PDU.
• Use hook-and-loop fasteners where necessary.
Note:
108 Power Systems: Site and hardware planning