HP FlexFabric 12900 series Installation Manual page 12

Make sure dimensions of the rack are sufficient for the chassis. To meet the clearance requirement,
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HP recommends that you use a rack with a depth of 1.2 m (3.94 ft). You must reserve at least 155
mm (6.10 in) of clearance between the front rack post and the front door.
The depth of the switch is 1080 mm (42.52 in) by calculating together the depth of chassis, the
cable management bracket, and the power cable bracket. For more information, see Figure 2.
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