Rack-Mounting the Switch
a standard rack-mount kit is included for mounting the switch in a standard 19-inch (48.3 cm) equipment rack with two unobstructed outer posts, with a nominal depth (between the front and rear mounting posts) of 19.25 inches (48.9 cm) and a maximum depth of 32 inches (81.3 cm). this kit is not suitable for racks with obstructions (such as a power strip) that could impair access to the field-replaceable units (frus) of the switch.
alternatively, you can obtain a 23-inch rack-mount kit.