2N VS N+1 – What’s The Difference?

Ahhh, how I love buzz words. We hear these constantly at the data center. I heard someone ask the other day, “What’s the difference between 2N and N+1?” You generally hear it said like “We have N+1 cooling.” or “We are 2N on our UPS.”

Sooooooo, what’s the difference? It’s pretty simple. N represents the exact amount you need, whether it be cooling or power or donuts.

If you are N+1, then you have the exact amount you need + 1 spare. N+2 would be the exact amount you need + 2 spares.

If you have 2N, then you have 2 * exact amount, or double the amount of equipment you need.

Pretty straight forward, but for those of you lost like a babe in the woods, well now you know…and knowing is half the battle. The other half is shooting people and lots of explosions and stuff. Which means that the more we learn, the more blood and guts there is…so to that end, we just need to dumb everything down.