Summary of the Amazon S3 Service Disruption

Re:Summary of the Amazon S3 Service Disruption by CobrastanJorji on Thursday March 02, 2017 @01:22PM (#13776675)

It's one of the reasons that silly guarantees like "twelve 9s of reliability" are meaningless. There are humans here. "Accidental human mishap" is gonna happen sometimes, and when it happens it's probably gonna affect a lot of data. Heck, at around 7 or 8 nines you have to account for the possibility that your operations team will decide that all your data is a vicious pack of timberwolves and needs to be defeated.

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Re:Summary of the Amazon S3 Service Disruption by andrewaylett on Thursday March 02, 2017 @01:41PM (#13776874)

Note that's durability not reliability. You might not be able to get at it with every request (I think 99.99% is the target) but it'll still be there if you try again later.

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Re:Summary of the Amazon S3 Service Disruption by idlewords on Thursday March 02, 2017 @01:50PM (#13776966)

The point is that at eleven nines, you're entering the realm of very rare/unlikely events that will also affect durability.

In other words, there's a lack of humility about "unknown unknowns".

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Re:Summary of the Amazon S3 Service Disruption by notatoad on Thursday March 02, 2017 @01:58PM (#13777055)

but amazon doesn't offer eleven 9s of availability. I don't think anybody serious does, so arguing how silly eleven 9s of availability is is kind of pointless. The SLA is only four 9s of availability.

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Re:Summary of the Amazon S3 Service Disruption by agrajag on Thursday March 02, 2017 @02:44PM (#13777519)

Not even four 9's - they only trigger SLA credits when they dip below 3 9's.

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Re:Summary of the Amazon S3 Service Disruption by simonebrunozzi on Thursday March 02, 2017 @01:30PM (#13776767)

Note: they say "S3 is DESIGNED for 11 9s of durability". It's PR-speak to say that they don't give you any guarantee, but in theory the system is designed in a magnificent way.

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Re:Summary of the Amazon S3 Service Disruption by cobookman on Thursday March 02, 2017 @02:57PM (#13777619)

11 9s of durability is about the likelyhood of AWS loosing your data. It doesn't cover the likelyhood of you being able to access your data that's called availability.

For example on GCS (Google's S3)...A storage class specifies how many locations the data is made available. All storage classes share the same durability (chance of google loosing your data) of 99.999999999%, but have different availability (chance of being able to retrieve data).

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Re:Summary of the Amazon S3 Service Disruption by majewsky on Thursday March 02, 2017 @06:21PM (#13779295)

> chance of google not loosing your data of 99.999999999%

git commit -m 'typo'

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Re:Summary of the Amazon S3 Service Disruption by Bartweiss on Thursday March 02, 2017 @02:18PM (#13777262)

I think it's a little better than that, actually.

It says that their ideal-case failure rate is 11 nines; that's how much you should lose to known, lasting issues like machines failing and cutting over.

Amazon's actual SLA offers 2 nines and 3 nines as the credit thresholds. So they're stating the reliability of their known system, and the rest is for events like this.

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Re:Summary of the Amazon S3 Service Disruption by dkersten on Friday March 03, 2017 @06:19AM (#13782120)

Durability and uptime are not the same thing. Durability is about the chance of losing your data and has nothing to do with service disruptions. Their uptime SLA is much lower. Looking at [1], it looks like the SLA says 3 9s (discounts given for anything lower) of uptime.

[1] https://aws.amazon.com/s3/sla/

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Re:Summary of the Amazon S3 Service Disruption by pavel_lishin on Thursday March 02, 2017 @01:25PM (#13776707)

As I understand it, those guarantees don't mean that the service will actually stay up for the given number of 9s; it's that you'll be reimbursed monetarily if and when they go down.

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Re:Summary of the Amazon S3 Service Disruption by SilasX on Thursday March 02, 2017 @01:33PM (#13776803)

I don't think it even means that; their policy says that the reimbursement only happens when your reliability dips all the way down to three 9s:

https://aws.amazon.com/s3/sla/

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Re:Summary of the Amazon S3 Service Disruption by dkersten on Friday March 03, 2017 @06:20AM (#13782126)

The SLA (as you linked) says three nines. The 12 nines quoted by others is durability, not uptime.

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Re:Summary of the Amazon S3 Service Disruption by HeyLaughingBoy on Thursday March 02, 2017 @01:32PM (#13776794)

Kinda the same thing, though. I mean, from my perspective there's no substantive difference between me saying "this service will stay up 99.xx% of the time and me buying insurance to pay you for the 0.xx% of the time I might fail.

The alternative is that I use the insurance to pay my legal fees when you sue me for not meeting my uptime guarantees.

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Re:Summary of the Amazon S3 Service Disruption by jstanley on Thursday March 02, 2017 @02:30PM (#13777369)

It's not the same thing. The Amazon service might only be costing you $100/mo, but if it goes down the cost to your business might be millions. They'll reimburse you the $100, not the millions.

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