For those of you who are regular visitors to this blog, this topic may seem rather basic. However, I was recently asked to write an article on this subject and thought that if it’s good enough for that venue then perhaps someone will find benefit in reading here as well. So here are some highlights from that piece-
Clients often come to us for help with data center consolidation or new data center implementation projects. The discussion quickly comes around to the appropriate “Tier Level” for their IT facilities. What we’re talking about here (to a large extent) is an industry standard way of describing the availability of the data center facility. Availability, in this case, is referring to the degree to which the facility can support constant uninterrupted operation of the contained data processing systems.
We know that the systems themselves can be architected with high-availability configurations. Autonomous failover of network connections, clustered server environments, and so on are ways that the systems can sustain operation even if, say, a server crashes. What the Tier Levels of a data center refer to though, is the capability of the facility itself to support the systems it serves. Utility power can fail, the temperature in the building can rise to cause damage to equipment, and so on. These are facilities issues, and are the foundation upon which any amount of data processing fault-tolerance stands.