Chapter 2 System Setup 21
About System Rackmounting
Youcan mount the server in any rack that meets the Electronic Industries
Association (EIA) standard specification 310 (EIA 310). The system enclosure
measures 6.95 inches high, 17.25 inches wide, and 27.25 inches deep (17.6 cm x
43.8 cm x 69.2 cm) and requiresa minimum of four vertical rack units (RUs—1 RU is
1.75 inches or 4.45 cm). The system has a maximum weight of 75 lb (34 kg).
Shipped with your system is the Sun Fire 280R Server Setup and Rackmounting Guide,
which describes how to rackmount your server.Use the guide for rackmounting
instructions.

Rackmounting Guidelines

■Install the slide assemblies for the first server in the lowest possible rack position.
■Forstability, install the remaining servers from the lowest system upward into the
rack, as shown in the next figure.
■Tomount the server in an EIA standard rack, allow four RUs per system to obtain
the highest density in the rack. Use the supplied Rack Buddy rackmounting
template to locate the correct holes for server placement in the rack.
Use the Rack Buddy to determine at what height in the rack you will install the
server slide assemblies (and other subsequent server slide assemblies).
For example, a Sun cabinet might have 36 configurable vertical RUs and could
support up to nine servers. Tomaximize server density in a 72-inch (182.8-cm) rack,
install the slide assembly brackets starting for the lowest enclosure at rail hole 9 (in
a rack configured with a power sequencer in holes 1 to 6), and add subsequent
brackets starting at rail holes 21, 33, 45, 57, 69, 81, 93, and 105. The following figure
illustrates such a configuration.