User guide

Rack information C–21
Hitachi Unified Storage VM Block Module Hardware User Guide
Preparing for installation
This section covers preinstallation guidelines to observe before installing the
equipment in a Hitachi rack.
Planning considerations
The following information will help you plan an acceptable equipment rack
configuration.
To ensure personal safety, maintain a low center of gravity, and reduce the
chance of instability, install the storage system controller and drive boxes
from the bottom of the rack upwards.
To ensure that internal heat build up is dissipated, do not restrict air flow
Be sure no vents are blocked, and that the HUS VM controller and drive
boxes are away from a solid surface such as a wall or partition. Air flows
through the units from front to rear.
• Enclosed racks must have adequate ventilation. Ensure that the rack is
not overly congested, because each unit generates heat. An enclosed
rack should have louvered sides and a fan to provide cooling air.
• In an enclosed rack with a ventilation fan in the top, excessive heat
generated by equipment near the bottom of the rack can be drawn
upward and into the intake ports of the equipment above it in the rack.
Provide adequate ventilation for equipment at the bottom of the rack.
• Baffles can help isolate exhaust air from intake air, which also helps to
draw cooling air through the chassis. The best placement of the baffles
depends on the airflow patterns in the rack, which can be found by
experimenting with different arrangements.
• Consideration should be given to the floor ratings of the site where the
rack and units will be installed. For information about the weight of an
example storage controller and drive boxes, see Floor load ratings on
page C-10.
Receiving the rack from the shipping carrier
To receive a fully integrated and configured Hitachi rack, consider the
following:
• The dock door at the receiving site must accommodate the height and
width of the rack.
Note 1. Also see the system Environmental specifications on page A-8.
Item Specification
Note: In the Hitachi rack, 2U is reserved at the base of the rack. This
leaves 40U of mountable space in the rack. Storage system units are
mounted starting from that point in the rack.