Data Center Tiers: Levels and Standards Explained

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Data Center Tiers: Levels and Standards Explained

In this article, we discuss the various types of data centers and which are appropriate for your application's needs.

· Big Data Zone ·
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The ability of a data center to preserve its functionality during different types of failures like power outages refers to data center tier. When tier levels are higher, it shows its ability to sustain data for center operations and fault-tolerant systems that will permit nonstop utilization during particular types of predicaments or emergencies. What can you expect from data center tier 1 or 2, and how does it differ from data center tiers 3 and 4. 

The data center standards generate some sort of stability depending on the level of service based on the tier type and necessities it can maintain. For a period of time, 4 different tier levels have been in existence, though tier 5 is coming up with new, innovative, and more durable needs, which will be explained in this article. We will be looking at the various standards so you have a clear comprehension of the different data center tiers.

Tier 1

Tier 1 data centers are in the last tier as a result of the level of severance and interruption they have. The system usually shuts down during power outages and emergencies, and it has just a single path for its power and cooling equipment. The structure also has to be totally turned off to carry out the yearly examination and renovation work of the building, triggering a possibly extensive stoppage. Its uptime is estimated to always be about 99.671% annually, which is equivalent to 28.8 hours of stoppage.

A lot of small businesses always love Tier 1 data centers since it is the most affordable option for hosting their servers. Though, the shortage of backups and redundancy can actually put the business at risk. A Tier 1 data center needs to be avoided if the company depends greatly on data.

Tier 2 

The Tier 2 data center has a slightly different uptime of 99.741%. It contains more structure and implements measures to reduce risk associated with potential outages as compared to Tier 1 data center. Added to that, a Tier 2 data center needs to have redundant (N+1) capacity parts (e.g., uninterruptable power supply (UPS), cooling systems, and auxiliary generators).

Generally, it has a single path for power and cooling with some redundant and standby parts. As an example, there could be a generator to serve as a standby power and cooling system to maintain the data center environment at its best. Users can expect a 22 hours annual downtime. Any part that fails to work properly can be fixed manually by changing to a redundant item with a small interruption period. Programmed repairs still need downtime, but it still provides a level of dependence that Tier 1 does not have.

Tier 3

Tier data center 3 has been designed to meet up with the shortcomings of data Tiers 1 and 2 and is what medium and bigger companies always tend to find preferable. Most of its equipment is dual-powered and contains several uplinks. With many paths for power, cooling, and systems intact, servers can stay functional during deliberate maintenance and outages. Thus, if one fails, there are others that the system can use to work. Some data centers even provide effusively problem-resistant equipment. They are typically referred to as Tier 3+ data centers in the flea market.

Tier 3 options have an estimated uptime of 99.982%, which comes out to 1.6 hours of downtime yearly. The cost is considerably inexpensive than Tier 4 data centers. Therefore, most businesses that need regular online attendance or full-time online operations usually go for Tier 3/Tier 3+ data centers.

All IT equipment also has several power bases in these data centers, and there are particular techniques in place to permit conservation and repairs to be carried out without necessarily turning off the system. There is often some type of power outage security in place, just like in Tier 3 facilities.

Tier 4

Tier 4 stands out as the maximum level of data center tiers and equally the most expensive. Tier 4 data centers can meet up to the needs of Tiers 1, 2, and 3, while equally ensuring that all equipment is completely fault-resistant. It is totally redundant with several cooling systems, sources of power, and generators to be on standby. 

Interruptions should not take place when there are prearranged maintenance and inadvertent outages. Tiers 4 has an estimated uptime of 99.995%, which is projected to be 26.3 minutes of downtime annually, which is just 0.013% greater than a Tier 3 data center. They provide a 96-hour power outage protection.

The redundancies built into Tier 4 data centers are designed to ensure that the system can work with no problems even if one or more pieces of equipment develop a fault. All are redundant, including generators, cooling units, and power sources, just to name a few. These are all in place so that an alternative system can instantly take over in case another fails.


To determine which data center to go for, there is a need to think about both availability and your IT needs. Tier 1 and Tier 2 data centers are not typically right for mission life-threatening workloads, except you have no other alternative and have emergency plan to deal with how the business works during interruptions. It is recommended that companies house all their critical workloads in Tier 3 and Tier 4 data centers only. It is preferable to pay for what can have all your data well protected so as to avoid any stoppages. It is also important that all companies have their data tiers maintained so as to avoid any unforeseen circumstances. Companies equally need to work with the best web hosting and data servers.

big data ,data center ,data center deployment ,tier

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