What Are Tier Ratings for Data Centers?

There are thousands of data centers around the world. While all data centers are used to house computer equipment, they’re not all the same in building or managing the same data.

Whether you’re building your own private data center, 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:

• Descriptions of each data center tier rating
• What the ratings are based on
• The importance of rating data centers
• Which rating to use and next steps

What Are the Different Data Center Tier Ratings?

Years ago, industry experts realized 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 guarantee an uptime of 99.671%. This tier is the lowest level and has relatively little redundancy and other built-in features. But a tier 1 certified data center is still far better than housing servers in a closet in the office or other area not specifically built for this type of operation.

These facilities are often used for non-critical systems as they’re much less expensive to build and maintain. Most facilities that 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, though.

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 annually. They 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, one 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, about 95 minutes (or less) of downtime each year — a massive improvement from tier 2. A tier 3 facility offers significantly higher levels of redundancy on all key data center components.

Tier 3 facilities must have redundant paths for power and cooling, like one main connection for utility power, then a diesel generator that kicks on immediately in a commercial power outage. It usually needs a UPS to keep power to key systems active until the diesel generator supplies the needed power. Similar full redundancy on cooling systems is needed to avoid outages in equipment failure or maintenance. There are many ways to provide redundancy to these key systems, valid as long as they operate properly.

What is the tier 4 data center rating?

A tier 4 facility is the highest standard for data centers, with fully redundant systems and often multiple sources of redundancy in place. This facility can guarantee 99.995% uptime — under 26 minutes of yearly downtime. A tier 4 facility should have all key systems on 2N redundancy; this fully mirrored system on standby operates 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 power sources should be backed up by a UPS system and some type of generator that can keep things running without interruption.

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 must 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 standard evaluations 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, with no set requirements on what specific technologies must be used, only what results they can produce.
• Vendor neutrality: Similarly, the ratings aren’t based on using 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 available things, the higher the rating can be.

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?

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

You may also need other cloud services, such as email, data storage, and more. Anytime you’re using a cloud service, you’re almost certainly accessing equipment housed in a data center. Also, you may wish 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 fine.

But if you’re running an e-commerce business and rely on your website to generate sales, it is best to be housed in at least a tier 3 facility. Finding the right balance between price and performance is always a challenge. However, for most 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, make sure you know what type of data center it operates. You can often tell 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 the sales team to ask about this important factor. Knowing the tier level helps you to choose the right service provider for all your web hosting and cloud needs.