Solution Convert your 2Post Racks into 4Post Racks using 2Post Conversion Kits.

Description 2Post Conversion Kits contain a set of 4 large brackets. These brackets provide the corner attachment that 4Post Rail Kits require. The brackets are available in several sizes from 2-7 Rack Unit heights and 3 different depths allowing you to purchase exactly the amount of space that you are going to use. If your server is 4 Rack Units tall, you will need a 4U Conversion Kit, for example. The drawing on the right shows what a 2U box will look like once it has been mounted on rails that have been attached to the 2U Conversion Kit.

The drawings above illustrate how to convert a 2 Post Rack into one that acts like a 4 Post Rack. In the example above, twenty, 2U, 2 Post Conversion Kits have been stacked on top of one another. The brackets have round holes on one end so that one side might be screwed into the threaded holes of the 2 Post Rack. The the other end of the brackets has square holes. Once the brackets have been mounted to the rack, the square holes will face outward in the front and rear of the rack, essentially now transforming it into a 4 Post. Cage nuts and screws are also included if threaded holes are necessary.

Server racks come in many different sizes. Some are as short as a 4U Desktop Rack and might only be 9″ tall. Others found in data centers may be as tall as 8 or 9 feet and allow for as much as 55U of equipment space. In many data center environments, rack space becomes important, as the need to rack more equipment such as servers, storage devices, network switches and PDUs is part of the daily challenge. In many instances, limited square footage can present a problem. So what do you do when you run out of floor space for additional server racks? You could go vertical. Why not consider replacing traditional size, server racks with taller server racks that accommodate more equipment without the need for additional floor space? The most common rack heights found in data centers are typically around the 42U to 44U range. By the way, one “U” or “RU” space is 1.75″ tall. So, by replacing a 42U with a 55U, you gain 13U (22.75″), or 30% more rack space. In cases where hundreds of racks or more are in use, that translates into lots of extra equipment space.

50U Open Frame Racks may be bayed together with two, 55U Racks, for example. All four server racks may be equipped with top Air dams, and the rack on each end also may have a side Air Dam installed. Air Dams act like an eave on top of the rack, sticking out 5″ – 10″. The side dams also protrude out 5″ – 10″.  Air Dams are used in tandem with floor grates to improve air containment. These racks may also have optional, side panels for enclosing the two ends of the bay of racks.

On the flip side

The front of a server rack loaded with equipment looks cool, but the back of the rack is where things can get a little hairy, and organization is key to keeping your sanity. That’s why it’s important that a rack have vertical cable bar options, a place to mount vertical PDUs and in some cases, LAN and Power assemblies for network switch ports, etc.

See Open Frame, 55U Racks for sale.

Wall Mount Racks typically come in Open Frame or Cabinet styles.  The Open Frame, Wall Mount Rack is an effective, less expensive, racking option, but it won’t necessarily keep your equipment secure. To discourage equipment tampering, add panels to the top, bottom and sides, as well as a front cover. Because it’s an “Open Frame” rack, equipment installation, wiring and cable management tend to be easier than with an enclosed cabinet, and air flow is not an issue.

What height do I need?

Wall Mount Racks are available in many sizes for use with several applications. Open Frame, Wall Mount Racks are configured by height and depth selections. Heights may range from 12U to 21U, for example. When selecting the height, you determine how much rack U space you need. A “U space” measures 1.75″. A Wall Mount Rack may let you mount up to 21U (36.75″) of equipment in the front rack space, for example. If you don’t require that much U space, you might consider a 15U or 12U height instead.

What depth do I need?

The depth of the Wall Mount Rack is measured in inches (or mm) since it’s important to know how much room is required to mount a piece of equipment in the rack. Before choosing a Wall Mount Rack depth, measure the depth of your equipment to make sure it will fit in the rack, and be sure to allow for a minimum of 3 inches in the back for cabling. Therefore, if you select a rack that is 10.5″ deep, your equipment should ideally be no more than 7.5″ deep.

Also, consider whether you anticipate adding equipment in the future. The size of the equipment you plan to add later, may help determine the size of the rack you need.

Note: The Wall Mount Rack shown below has additional U space on the top and bottom that may be used for equipment such as patch panels or power strips.

Mounting a Wall Mount Rack

The best thing about the Wall Mount Rack is that it can be mounted on a wall (or almost any flat surface), which means it takes up less space and stays out of your way. Depending on the size you select, a Wall Mount Rack may support 300 – 400 lbs of equipment. I recommend you review the installation instructions prior to purchasing a Wall Mount Rack to make sure they correspond to your preferred mounting configuration and location. Typically, the Wall Mount Rack will come with assembly, mounting and rack mount hardware, but I suggest you review the product documentation to be certain.

What kind of equipment can I put in a Wall Mount Rack?

Wall Mount Racks are primarily used for racking network equipment such as switches or patch panels, but servers may also be mounted vertically in a Wall Mount Rack. Notice in the photo below how the power strip is mounted on the top of the rack.

This 12U x 4U Wall Rack has four, 1U servers mounted vertically.

Tool-less Filler Panels may be used to enclose the open spaces in the Wall Mount Rack. In the photos below, a 3U filler panel was added to mostly enclose the 4U top of the rack, but 1U of space was intentionally left open.

See Open Frame, Wall Mount Racks for sale online.

The main benefits of open frame racks are:

• low cost
• easy access to cabling
• unrestricted airflow optimizes cooling
• ease of installation
• shipping costs are less

The main disadvantages to open frame racks are:

• lack of security
• cosmetic – enclosed racks have a cleaner look

Open frame racks can be coupled together with a simple, inexpensive, baying kit, making them ideal for data centers. The cable management on an open frame, equipment rack is very simple. A vertical, cable management bar is typically included and provides an innovative and simple means of routing any type of cables.

Open frame racks typically have a fixed mounting depth. The most common depth is 29″ which is compatible with modern equipment from all OEMs. The equipment racks usually have square mounting holes and use cage nuts.

Open frame racks come in several sizes:

Most recently, a 55U open frame rack has become available.

Here’s an example of what the rear of an open frame rack, filled with servers and equipment, might look like.
This one is shown coupled together with a second open frame rack.

Here’s a great example of three open frame racks bayed together in a server room.

Links to More Information:

• List of Rack Types
• Why all racks are not created equal
• What is a 19″ rack

When dealing with server rack technical support, you hear the term “standard rack” every day. A customer will say “I don’t know why my server won’t fit. I have a standard 19″ rack”. The problem lies in the fact that, although there is a document defining standardized 19″ racks, there are a lot of details left out of the specifications. The standard is EIA-310.

What the EIA-310 Rack Standard does not include

Here is a brief list of rack details not completely defined or addressed:

• Does the rack have 2 posts, 4 posts, or even 6 posts
• How deep is the rack’s mounting depth
• What is the thread type of the rack
• Are the rack holes threaded, square or round
• What is the shape of the rack upright: “L”, “C”, or “?”
• Are there obstructions between the front and rear posts
• How much space is between the front door and the front post
• How much space is between the rear door and the rear post

Problem #1 – Rack Holes

Rack hole type is the number one reason for server and rack incompatibility. This is why we always recommend square hole racks. You can always add threads with a cage nut if you need them. Most modern server rails are designed for square holes. Only a few OEM rails are compatible with both round and square holes.

As an example:

• Dell’s RapidRails only work in square holes.
• Dell’s VersaRails work in round, non-threaded holes, but not threaded holes such as 10-32 or 12-24.
• Dell now has a combo rail that can switch between Rapid and Versa, but still does not work with threaded holes.

The solution is often to find a third-party rail for the server or use a fixed rail kit.

Problem #2 – Uprights and Obstructions

The second most common type of server and rack incompatibility is rack obstructions. The EIA spec does not address what the rack manufacturer does between the front and rear mounting posts. There are often additional flanges or other mounting features. These obstructions are notorious for colliding with the OEM’s slide rail and preventing the installation.

Again, the solution is often to find a third-party rail for the server or to use a fixed rail kit.

Problem #3 – Rear Door Collision

If I only had a dollar for ever time I heard, “The server fits fine. Except the back door of the rack won’t close”. This problem is caused by competition among the OEMs to fit as much technology as possible into a 1U or 2U server. They cannot make the box wider or taller, but they can make them deeper. And every year, the servers get even deeper until racks can no longer hold them. In the 1990′s, a 36″ deep rack worked great. In the early 2000′s a 39.37″ (1 meter) rack was the standard. Now racks are being sold as deep as 42″ and 44″ deep.

The solutions to this problem are limited, but there are a few (If only we had invented a “Rack Stretcher”) . Options include:

• Sometimes the Cable management arms can be removed
• The back of the rail can be cut off (we do this all the time for Dell 1950 and 2950)
• Fixed rails can be used

More Information

• What is a 19″ Rack
• What is a Rack Unit (“U” or “RU”)
• What is EIA-310
• Wikipedia has an in-depth overview of 19″ racks
• Why all racks are not created equal

Solution: The Dell OptiPlex comes in four different sizes; the UltraSmall Form Factor (USFF), the Small Form Factor (SFF), the Desktop, and the MiniTower (MT). Only the USF and SFF are small enough to make a reasonable sized All-In-One. Dell sells the following All-In-one kits through S&P (software and peripherals).

Dell S&P P/N A0728637 - OptiPlex SFF + LCD monitor
Dell S&P P/N A1149268 - OptiPlex SFF + LCD monitor + Cover
Dell S&P P/N A0985007 - OptiPlex USFF + LCD monitor

These kits will work with any monitor that has a 75mm or 100mm VESA mounting pattern. This includes all currently available Dell monitors. The kit has been tested with monitors as large as 30″ with no adverse effects on stability or usability.

It’s time to install your server and come to find out someone has tossed the rail kits. After hours, days, or even weeks of searching you find out that the OEM rail kits are no longer available.

At this point, frustration sets in and you are afraid your only option is to stack the server on top of another server. One option is to put the server on a shelf but this usually means wasting a U space just for the shelf. Another option is using non sliding rail kits. These rail kits are compatible with practically all racks, including 4post and 2post racks with round or square holes. You can still easily slide the server in or out of the rack for maintenance. The rails kits just do not telescope in front of the rack like a lot of original rail kits.

Most desktop PC’s are not designed to be converted into a rackmount server. Sliding rail kits are simply not an option due to the design of the chassis. In most cases the PC can be placed on it’s side on a shelf, that is if it does not exceed 17.7″ in width, which is the opening of an EIA standard 19″ rack.

Rack Mount a PC Vertical

If the PC is in fact wider than 17.7″, another option is to stand the unit upright on the shelf. In this scenario, you can actually place 2 PC’s side by side, again, that is if the overall width of both does not exceed 17.7″. Of course, not all PC’s weigh the same so make sure to weigh the PC before purchasing a rack mount shelf. Below are a few options of sliding shelves.

Things to consider when Racking a PC

• Will the shelf mount in your rack’s hole type and mounting depth
• How deep is the shelf
• Will the shelf us an additional U of rack space
• Do you need telescoping rails or a fixed shelf
• Will the PC be attached to the shelf
• Does the shelf kit include anti-slip mats
• Are cable management arms important

EIA stands for the Electronic Industries Association. The current revision is EIA-310-D. The EIA-310 document is available for purchase at the IHS website.

Overview

EIA-310 is a specification for what is often called the “standard rack”. This specification standardizes several important features of 19″ racks, such as the Rack Unit (RU or U), vertical hole spacing, horizontal hole spacing, rack opening and front panel width. The specification also sets tolerances on each of these dimensions.

The EIA-310 specification has been the 19″ racks standard for equipment for 50 years. Despite this, RackSolutions believes that the items that the specification does not cover is the real reason for the industry wide incompatibility we now face. Rack features such as hole type, rack mounting depth, front and rear space, and obstructions between front and rear rails are the cause of real rack headaches.

Vertical Hole Spacing

Vertical hole spacing is defined as a repeating pattern of holes within one Rack Unit of 1.75″. The hole spacing alternated at: 1/2″ – 5/8″ – 5/8″ and repeats. The start and stop of the “U” space is in the middle of the 1/2″ spaced holes. See the diagram below.

Horizontal Spacing

The horizontal spacing of the vertical rows of holes is specified by EIA-310 at 18 5/16″ (18.312)(465.1 mm). This dimension is not well maintained on some racks, causing problems with equipment installation. Many manufacturers use equipment mounting slots instead of holes to allow for variations in this dimension.

Rack Opening

The opening in the rack is specified as a minimum of 17.72″ (450mm). 2Post or relay racks tend to have a larger than normal opening, as do many other racks with threaded holes. Square hole racks tend to be very close to the minimum opening.

Front Panel Width

The only dimension on a 19″ rack that actually measures 19″ is the width of the front panel of equipment.

More Information

• What is a 19″ Rack
• What is a Rack Unit (“U” or “RU”)
• Wikipedia has an in-depth overview of 19″ racks.
• Why all racks are not created equal

]]> http://www.server-racks.com/eia-310.html/feed 16 http://www.server-racks.com/19-rack.html http://www.server-racks.com/19-rack.html#comments Wed, 10 Oct 2007 21:39:21 +0000 bob http://www.server-racks.com/19-rack.html Description:

The funny thing is . . . Nothing on a 19″ Rack measures 19 inches. The term 19 inch comes from the width of the front panel of the boxes that are installed in the rack (see the image below). To determine if your rack is a 19″ rack, measure the hole to hole spacing.

Rack hole-to-hole spacing:

19″ Rack = 18-5/16″ (18.312″) (465.1 mm)
23″ Rack = 22-5/16″ (22.312″) (566.7 mm)
24″ Rack = 23-5/16″ (23.312″) (592.1 mm)

More Information

• What is a Rack Unit (“U” or “RU”)
• What is EIA-310
• Wikipedia has an in-depth overview of 19″ racks.
• Why all racks are not created equal