1.6 Reviewing the Cable Management Arm Guidelines

Review the following cable management arm (CMA) guidelines before routing the cables.

• Remove all required cables from the packaging, and allow cables to acclimate or reach operating temperature, if possible. The acclimation period is usually 24 hours. This improves the ability to manipulate the cables.

• Label both ends of each cable using a label stock that meets the ANSI/TIA/EIA 606-A standard, if possible.

• Begin the installation procedure in ascending order.

• Only slide out one server at a time. Sliding out more than one server can cause cables to drop cause problems when sliding the servers back.

• Separate the installation by dressing cables with the least stringent bend radius requirements first. The following bend radius requirements are based on EIA/TIA 568-x standards, and may vary from the manufacturer's requirements:

  • CAT5e UTP: 4 x diameter of the cable or 1 inch; 25.4 mm minimum bend radius

  • AC power cables: 4 x diameter of the cable or 1 inch; 25.4 mm minimum bend radius

  • For X8M and later, with RoCE Network Fabric:

    • 30 AWG: Single cable diameter of 4.5 +/- 0.2 mm and lengths from 1 to 3 meters; 21 mm single bend minimum bend radius or 45 mm repeated bends.

    • 26 AWG: Single cable diameter of 5.8 +0.3 mm/-1.0 mm and lengths from 2.5 to 5 meters; 29 mm single bend minimum bend radius or 58 mm repeated bends.

  • For X8 and earlier, with InfiniBand Network Fabric:

    • TwinAx: 5 x diameter of the cable or 1.175 inch; 33 mm minimum bend radius.

    • Quad Small Form-factor Pluggable (QSFP) cable: 6 x diameter of the cable or 2 inch; 55 mm minimum bend radius.

    • Fiber core cable: 10 x diameter of the cable or 1.22 inch; 31.75 mm minimum bend radius for a 0.125 cable.

• Install the cables with the best longevity rate first.