Many data centers historically didn't put much more thought into their deployment of server racks beyond basic functionality and the upfront costs of the rack itself. When compared to a data center's complex mechanical, electrical, and technical systems, a server rack is low on the totem pole of strategic commodities.
But this perception is belied by a few simple facts. Server racks house millions of dollars worth of hardware, safeguarding all processed data, transactions, and intellectual property. They are the definition of "physical" infrastructure-welded steel that serves as your enterprise's last line of physical security. Finally, and most importantly, no cooling approach can exist without taking the server rack into account.
Server Rack Cooling
The only ASHRAE temperature standard exists at the equipment inlet-the front door of the rack. While the cooling process doesn't necessarily start there, nowhere is it more important. IT professionals, when considering a rack manufacturer and product, need to understand how that product contributes to productive cooling. Here are some telltale questions and scenarios:
- Does the rack product have proper features for conventional, convective cooling? Server manufacturers recommend a 64% perforation pattern on the front door for optimal airflow.
- Does the rack have inherent features that contribute to hot air recirculation? Racks as narrow as 24" have openings along the perimeter that must be sealed to separate hot and cold air paths. Blanking panels should be installed in all vacant rack spaces (RU).
- Does the rack manufacturer have cooling products that scale? If, through a hardware refresh, a 4kW rack load becomes 12kW, does your rack manufacturer have a supplemental cooling solution? Can you add capacity without a major overhaul?
- Does your rack manufacturer offer next generation cooling technologies (In-Row, In-Rack, Liquid Cooling) for day-one high density loads? A recent study by Emerson states that future data centers will be designed to support between 10-20kW per rack-far beyond the capabilities of conventional cooling designs
Your choice of manufacturer and product today can save you time and heartache in the future. 42U's sales engineers are server rack and data center power/cooling experts. They will collaborate with you to determine which of the leading rack manufacturers' enclosures will best secure your key IT assets as well as address current and future capacity issues. 42U can help you ensure that the racks you select are the best solution for your current and future capacity and security needs.
Server Rack Considerations
Space utilization, flexibility, and lead time are also important rack talking points. The following recommendations speak to these points.
Install the maximum footprint possible.
Servers continually get smaller and more powerful. Meanwhile, the support requirements at the rack level continue to increase: more power circuits, larger whips, more cables to manage. Installing the maximum practical footprint, in terms of width and depth, provides the most flexibility in the future for ever-changing hardware requirements.
The rack footprint, of course, must be weighed alongside real estate policies and costs. Data center floor space is expensive, and larger cabinets will consume more of it.
Make use of "Tool-less" features.
At one time, users needed a tool belt to work on server racks. Now, a number of manufacturers offer "tool-less" rack features to simplify installation. Rack PDUs, cable managers, shelves, and other rack components (like side panels and roofs) can be installed without screwdrivers or small hardware.
These tool-less features are not ubiquitous, so please consult 42U for more information on participating manufacturers and products.
Understand all rack features.
Each manufacturer's solution is different. If you are considering a new product, make use of spec sheets and engineering drawings to understand the differences. For instance:
- Dimensions: Cabinet depth includes both the front and rear doors. Clarify published depth versus useable depth.
- Mounting Rails: Most racks have a preset position of 29" from the front to rear EIA rails. But ultimate rail spacing depends on your equipment. Do you need different spacing? Can the rails be preset at the manufacturer to accommodate your needs?
- Cable Management: Are there sufficient openings (either below or above) to accommodate cable ingress and egress? Are wider/deeper cabinets available for networking cabinets?
- Power Distribution: Does your rack have built-in hardware for PDU installation? If not, specify mounting hardware at the time of order.
- Hardware: Are you connecting cabinets together? Bolting them to the floor? This hardware is traditionally sold separately from the rack and must be specified by the user.
- Transport: Do you need casters to get racks from the loading dock to the data center?
Understand your manufacturer's capabilities.
Some manufacturers have limited product offerings. They have a few SKUs with no customization. Other manufacturers have assemble-to-order programs, where they can turn any number of rack configurations quickly. Users can specify unique components (like doors and roofs) and add ancillary products (like casters, cable managers, and power strips) to be pre-installed. The unit arrives at your site ready to use.
In these cases, your manufacturer can save you time and money on integration.