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There are thousands of data centers around the world used to run a huge number of different things. While all data centers are used to house computer equipment, they’re not all the same in building and managing.

Whether you’re building out your own private data center, you’re looking to have your website run in a third-party data center, or want to take advantage of advanced cloud technologies; you need to understand data center tier rankings.

Key Takeaways

  • A data center tier rating was established to help ensure companies and customers can get the level of service they need.
  • Any data center that wants to receive an official tier rating needs to have an unbiased evaluation performed by an authorized third party.
  • Data center tier ratings are established by the Uptime Institute’s tier certification standards, they come to the facility and scrutinize every aspect of the facility such as performance, tech neutrality, vendor neutrality, and redundant systems.

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What Are the Different Data Center Tier Ratings?

  • Tier 1 Data Center Rating – Lowest level; Max guaranteed uptime of 99.671%
  • Tier 2 Data Center Rating – Max guaranteed uptime of 99.741%
  • Tier 3 Data Center Rating – Max guaranteed uptime of 99.982%
  • Tier 4 Data Center Rating – Highest level; Max guaranteed uptime of 99.995%
datacenter to prevent server outage
Source: Reliablesite.net

Years ago, industry experts realized that some types of services need extreme stability levels while others aren’t nearly as critical. A data center tier rating was established to help ensure companies and customers can get the level of service they need.

What Is the Tier 1 Data Center Rating?

A tier 1 rating data center can only claim to guarantee an uptime of 99.671%. This tier is the lowest level data center and has relatively little redundancy and other features built-in. But, a tier 1 certified data center is still going to be far better than housing servers in a closet in the office or other area that’s not specifically built for this type of operation.

These types of facilities are often used for non-critical systems as they’re much less expensive to build and maintain. However, most facilities that would get a tier 1 certification won’t pay to go through the actual evaluation process since there would be little benefit to holding the certification.

What Is the Tier 2 Data Center Rating?

Tier 2 certified facilities can guarantee an uptime of 99.741%, translating to about 1,360 minutes of downtime per year. Tier 2 data centers must have some redundancy options to minimize the amount of downtime they experience.

In most cases, a tier 2 facility relies on a single power source, a single cooling source, and potentially multiple circuits for Internet connectivity. Despite the single sources for key systems, they often have built-in fail-safes, such as uninterruptible power supply (UPS) modules, cooling chillers, energy generators, and more.

What Is the Tier 3 Data Center Rating?

Tier 3 data centers can guarantee 99.982% uptime, which means about 95 minutes (or less) of downtime each year. This is a massive improvement from the tier 2 rating. At this level, a facility offers significantly higher levels of redundancy on all key components of the data center.

Tier 3 facilities must have redundant paths for both power and cooling. For example, a facility may have one main connection for utility power, then a diesel generator that kicks on immediately in the event of a commercial power outage. In most cases, the facility should also have a UPS system to keep power to key systems active until the diesel generator can supply the needed power.

Similar full redundancy on cooling systems is needed so that there are no actual outages in the event of equipment failure or maintenance. There are many ways to provide redundancy to these key systems, and as long as they operate properly, they’re all valid options.

What Is the Tier 4 Data Center Rating?

A tier 4 facility is the highest standard for data centers. They have fully redundant systems and often multiple sources of redundancy in place. A tier 4 facility can guarantee 99.995% uptime, which means less than 26 minutes of downtime per year.

A tier 4 facility should have all key systems on 2N redundancy, which means a fully mirrored system that’s on standby and operates completely independently of the primary system.

In most cases, this means two entirely separate sources of commercial power, two full cooling systems, and more. In addition, each of those commercial sources of power should be backed up by a UPS system and some type of generator that can keep things running without interruption.

room with server hardware
Source: InMotion Hosting

Understanding the Data Center Tier Ratings

Data center tier ratings are established by the Uptime Institute’s tier certification standards. Any data center that wants to receive an official tier rating needs to have an unbiased evaluation performed by an authorized third party.

They come to the facility and scrutinize every aspect of the facility, including things like:

  • Performance: Ratings are based on the performance capabilities of the facility. These are standard performance evaluations that are the same regardless of location, company ownership, the intended use of the facility, or other factors.
  • Tech neutrality: The tier ratings are technology-neutral, meaning there are no set requirements on what specific technologies need to be used, only what results they can produce.
  • Vendor neutrality: Similarly, the ratings aren’t based on using any specific vendors or services for the work and solutions provided.
  • Redundant systems: One of the key aspects of data center tier ratings is the redundancy of key systems. The more redundancy for power, cooling, connectivity, and other things that are available, the higher the rating can be.
Bearded Data Center IT Professional Walking Through Server Rack Corridor with a Laptop Computer. He Stops and Wirelessly Inspects Working Server Cabinets.
Source: Photostockeditor

Data centers don’t need to be officially certified at any specific level to operate. Many private facilities, for example, choose not to go through the certification process. However, a facility cannot claim to be certified as any tier without getting evaluated.

Some industries must use data centers that are certified at a certain level. For industries that directly impact consumer information, government agencies often require the data centers used to be at least tier 2.

Understanding what each tier rating consists of helps you see the value of getting this ranking type.

Why Is It Important to Rate Data Centers?

As more companies start using cloud technologies or colocation services, they need to know how stable the environments will be. A precise definition for each tier level allows companies to evaluate their options and decide which type of facility they want to use.

Using a tier 2 facility may be great for some companies because they don’t need extreme levels of reliability and would rather save money on paying for the services. Other companies, however, want to pay the extra money to ensure they experience virtually no downtime, so they opt to build or work with a tier 4 facility.

How Can My Small Business Benefit From a Data Center?

bare metal server
Source: Vhosts.vn

Small businesses should be using at least some services from a data center. Your website should be the most common way that your business benefits from a data center. All of the best web hosting services operate out of a data center. In most cases, web hosting facilities are going to be tier 3 or above since uptime is very important for websites.

You may also want to use other cloud services, such as email, data storage, and more. Anytime you’re using a cloud service, you’re almost certainly accessing equipment that’s housed in a data center.

Of course, you may also want to build out your own small data center to support your internal information technology (IT) equipment.

Which Tier Rating Should You Use?

The tier rating you use depends on what type of services you require and how critical they are. If you’re publishing a website for your business that’s rarely accessed and provides basic information to potential customers, hosting it in a tier 2 facility may be just fine.

However, if you’re running an e-commerce business and rely on your website to generate sales, you want it housed in at least a tier 3 facility.

Finding the right balance between price and performance is always a challenge. However, for most types of small businesses, utilizing either a tier 2 or tier 3 facility provides the right opportunities.

What Should You Do Next?

If you’re thinking about signing up for any type of cloud- or web-based service, you want to make sure you know what type of data center they operate. You can often tell just by looking at what type of uptime guarantee they promise for web hosting services.

If the tier level of the data center isn’t identified on the company’s website, don’t hesitate to reach out to their sales team to ask them about this important factor. Knowing the tier level helps you to choose the right service provider for all your web hosting and cloud needs.