Visit to the data center

Greetings to this great community. The popular saying that ignorance is no defense seems to be more pronounced in this our era. A simple display of ignorance to any of the new technology springing up these days and you will make headline or find your picture in people's whatsapp status, lol. Hence, as your number one ICT blogger, I see it as my onus to educate us on some of the infrastructures you're likely to see or use in a visit to the data center and common behaviors expected that an average individual should exhibit therein.

If you work in the data center or have been visiting the data center, then you may pass but I assure you, it will be an interesting read.

^{image source Pexels. CCO creative commons license.}

The data center is a place not meant for everyone, not even for many IT officials an organization, as such, it is okay to be ignorant or know little about the place. It is one of the most heavily guarded part of an organization and entry is usually strictly an authorized move. This is because of the costs of most of the equipment in the center and also due to the amount of information it houses. So let's begin.

Your Shoe could destroy the whole system!

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Before entering the data center, look carefully for some signs and cautions displayed at the entry. Many standard data centers don't allow every type of shoes into their data center. This is because of Electrostatic Discharge (ESD). Most of us at tender ages performed a tiny experiment using the pen and a little piece of paper. When the pen is rubbed against the hair, it generates high electrostatic charges whose effect can be felt by taking the pen close to the piece of paper and in effect, the pen magnetizes the paper.

Most floors at the data center are designed to discharge most accumulated electrostatic charges but naturally, they build up as we walk around the data center. Well, electrostatic discharge is the transfer of accumulated charge from one body to another at different potentials which is usually initiated by contact or through electrostatic field.

We experience this phenomenon everyday but the charges accumulated and discharged are usually not harmful to us but when we touch a server, these charges can be passed to them cause in many can render the server unusable. Our PCs are well insulated but most servers are bare metal which highly conductive. Apart from sending charges to the systems, the systems could also loose some charge to you and the ground which could also render them useless.

To avoid this, expect some data center attendant to ask you to pull your shoe and wear a special shoe known as electrostatic discharge shoe. Most data center has special floor that can safely discharge accumulated charges on these special shoes to the ground. Also you could be provided with an electrostatic discharge wrist band or both wrist band and shoe. The electrostatic wrist band are metallic conductors capable of discharging electrostatic charges as they build up.

The Floor and The Roof

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Hey man, you're probably standing on multitudes of cables! There are thousands of connections in the data center for both data and power. To make things look tidy, special floors called Raised floors and overhead Cable Trays are designed to concede these cables in a very professional manner.

In the raised floor system, a metal grid system, usually 5ft by 5ft grid system, where data cables, electrical conduits, pipes for running cooled water and even cooling systems can be installed under this raised floor. Some of the raise floors are perforated to enhance the cooling system. All the cables running underground terminate on the rack where they are intended to be terminated, hence it is very difficult to see the cable structure of data centers running the raised floor system.

Overhead structured cabling system also called cable tray system consists of flat metal trays constructed to run at the terminating points of conduits and trunks in order to carry cables that emerged from them. Unlike the raised floor system, the overhead installations always leaves the cables exposed but appears very tidy. Overhead installations are seldom used because it possess problem of cooling.

The Temperature

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Hey man, grab a jacket, you're going into a data center! The cooling systems found in data centers are not the same with the comfort cooling system found in our homes though it should be conducive enough for administrators but not always advisable to spend lengthy periods in the data center. IT equipment especially the servers don't usually come with fans like our personal computers do. They also comes with temperature sensing chips which automatically turns the server off in unfavorable conditions and I guess you won't imagine what it would look like having a server shutdown on its own with being planned. Millions or Billions could be lost!

^{An overhead cooling system. Image source Pixabay. CC0 creative commons license.}

The CRACs or the computer room air conditioning systems are usually located beneath the floor with vents for taking out heats generated by the equipment or cooling provided by normal air conditioners fastened to the wall or overhead cooling systems. Much energy is spent cooling IT equipment, most times, the amount of energy spent in cooling the whole systems are higher than the actual power consumed by equipment being cooled.

Modern cooling systems you will probably encounter in the data center is the underground cooling where cooled are is pushed through the perforated grid raised floor system. Typical average temperature of the data center is always below 25 degrees Celsius. Any temperature above that would compromise the operations of some temperature sensitive equipment.

The infrastructures

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In this section, I will introduce you to likely equipment you're likely to encounter and their functions.

• The Servers:

  A server is basically a computer, of course, but not like your PC. Servers are meant to perform specific tasks hence we have the popular web servers, network servers, print servers and so much more earning them the name “dedicated”. Any computer can potentially be a server. When you create hotspot with your computer or phone and other devices can connect to it, the gadget becomes a form of network server.

  
  ^{Blade servers. Source Flickr. CC BY-SA 2.0 license.}

  Hence servers performs the function of sharing resources and the device receiving this services is called the client. We are all clients to steemit server. The servers you will find in the data centers might not have the shape of the computer you’ve seen on normal computing environment. While some servers have desktop shapes, many are designed to be only coupled to the racks and hence are called Rack servers. We also have blade servers which are specially designed to minimize rack space and also consume less amount of power.

• PDU (Power distribution unit):

  You might have already noticed that there are hundreds or thousands of computers and devices in the data center. These devices probably needs electricity to operate. The mains distribution unit as PDUs are sometimes called are devices where multiple power cables are terminated with sole function of providing electrical power for the connected terminals.

  
  ^{A UPS PDU. Image source Wikimedia CC3.0 license.}

  As simple as powering up IT equipment might sound, managing, protecting and monitoring power systems in the facility is always a challenge for many firms, hence, data centers rely on this power distribution system to improve overall power efficiency.

  There are many different types of power distribution unit which includes Rack coupled PDUs and raised floor mounted power distribution units. The rack coupled PDUs as the name implies provides power to the equipment found in the rack and mostly takes power from the floor mounted power distribution units. The floor mounted power distribution units provides many functionality like intelligent power metering system, power filtering load monitoring and balancing, etc.

• Cables:

  The data center is infested with cables. Even wireless systems have power connection cables making the whole center saturate with cables. A big thanks to the raised floor and cable trays. A very popular cable found in the data center is the Category 5, 5e, 6, or 7 cables.

  
  ^{Image source Pixabay. CC0 creative commons license.}

  These are always black or blue in color though it might spot other colors like red, orange, green and yellow but most category cables are black and blue in color. Their terminals are always connected to a server, router or switch.

  Another cable you might see in the data center is the power cables. These cables usually originate from the power systems like the power distribution units (PDUs), stabilizers and power extensions. Special care should be taken when handling these cables since it could shutdown important system or you could get yourself electrocuted.

• Racks:

  A rack consists of electrical, electronic and mechanical systems. Mainly, a rack is metallic structure that houses IT equipment like the servers, switches, routers, cables, remote monitoring systems like sensors and cameras, etc.

  
  ^{A 42U rack. Image source Wikimedia. CC2.0 license.}
  Racks are classified by their housing capabilities or better still their number of bays or units. Hence, at the lowest rank, we have 4U racks and at the apex we have 42U racks. The 42U racks are mostly found in the data center and they’re usually seen as metallic structures standing about 1.4 meters high housing the above and under listed equipment.

• Routers and Switches:

  A server or generally a computer without a network is functionally incomplete. The services provided by the servers are meant most of the times to be used miles away hence, networking is provided to take care of this need. The routers and the switches perform this functionality.

  
  ^{a network router. Image source Pixabay CC0 license.}

  Most routers and switches looks very much like the blade servers though most of the time, they are sleeker than the blade servers. The router and the switches always have lights at their ports, these lights helps indicate the condition of the connectivity between the port on the router or switch and the device connected to it. Most common lights seen on the routers and the switches are amber and green. The lights always blinks giving even further information about connection status. When the lights on the ports are blinking very fast or not blinking at all (just steady in On mode), this is a very clear indication that there is a connection problem.

  It is always very difficult even for IT administrators to distinguish between switches and routers but most of the times, the routers always have few ports on them and have more sophisticated ports that looks like VGA ports on our computer (serial ports). The switches on the other hand have many ports on them and are designed to connect as many equipment as possible.

• Surveillance system :

  Security is a very serious concern when it comes to the data center, so mind your steps and actions, you're probably being watched. Their are many sophisticated cameras available in the data center including cameras with infrared for detecting motions and night vision capabilities.

References

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1. Electrostatic Discharge (ESD), Humidity and the Data Center
2. Data center cooling methods
3. Data center infrastructure management
4. Rules and regulations of the data center