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Data centers are too reliable

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Re: Data centers are too reliable

#2

Post by TamDenholm »

I wonder if its cheaper (and/or better) for a hosting provider to spend less on reliability and instead build in multiple redundancy. Thoughts?

Also, i've never heard the expression 4 nines before, anyone explain that for me?

Re: Data centers are too reliable

#3

Post by Hovertruck »

TamDenholm wrote: post #2

I wonder if its cheaper (and/or better) for a hosting provider to spend less on reliability and instead build in multiple redundancy. Thoughts? Also, i've never heard the expression 4 nines before, anyone explain that for me?

I assume it refers to uptime, e.g. 99.99% uptime.

Re: Data centers are too reliable

#4

Post by tangothedog »

TamDenholm wrote: post #2

I wonder if its cheaper (and/or better) for a hosting provider to spend less on reliability and instead build in multiple redundancy. Thoughts? Also, i've never heard the expression 4 nines before, anyone explain that for me?

It's a common way to describe uptime. It means 99.99% uptime/availability, which works out to under 1 hour of downtime per year.

http://en.wikipedia.org/wiki/Nines_(engineering)

Re: Data centers are too reliable

#5

Post by mdda »

TamDenholm wrote: post #2

I wonder if its cheaper (and/or better) for a hosting provider to spend less on reliability and instead build in multiple redundancy. Thoughts? Also, i've never heard the expression 4 nines before, anyone explain that for me?

4-nines is 99.99% reliability (downtime of about 1 hour per year). More detail :http://en.wikipedia.org/wiki/High_availability

Re: Data centers are too reliable

#7

Post by esrauch »

TamDenholm wrote: post #2

I wonder if its cheaper (and/or better) for a hosting provider to spend less on reliability and instead build in multiple redundancy. Thoughts? Also, i've never heard the expression 4 nines before, anyone explain that for me?

The number of nines refers to how reliable something is. "Four nines" means that it is up 99.99% of the time, or 0.01% of downtime, which is 0.0001 * 365 * 24 = just shy of 1 hour of downtime per year (or 1 day downtime every 30 years).

These things are usually specified in SLA (service level agreements) where if the provider exceeds the amount of downtime in the SLA means that you don't have to pay. If Amazon has a 4-nines SLA that means that you don't get any discount if they have 1 hour down per year.

Re: Data centers are too reliable

#8

Post by pdenya »

Link bait headline. Obviously the issue here is that Data Centers are not reliable enough. A good failover option is necessary but generators and UPSs don't represent the primary costs behind data centers, removing them won't come close to cutting prices in half.

The point seems to be to expect failure and make sure you're prepared but increasing the likely hood of failures for a slight decrease in cost is not a good way to go about it.

Re: Data centers are too reliable

#10

Post by pavel_lishin »

TamDenholm wrote: post #2

I wonder if its cheaper (and/or better) for a hosting provider to spend less on reliability and instead build in multiple redundancy. Thoughts? Also, i've never heard the expression 4 nines before, anyone explain that for me?

> I wonder if its cheaper (and/or better) for a hosting provider to spend less on reliability and instead build in multiple redundancy. Thoughts?

Wouldn't it look the same from my end?

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