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Comment by djsumdog | Hacker News Reader

Back when S3 failures would take town Reddit, parts of Twitter .. Netflix survived because they had additional availability zones. I can remember the bigger names started moving more stuff to their own data centers.

AWS tries to lock people in to specific services now which makes it really difficult to migrate. It also takes a while before you get to the tipping point where hosting your own is more financially viable .. and then if you trying migrating, you're stuck using so many of their services you can't even do cost comparisons.

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Netflix actually added the additional AZs because of a prior outage that did take them down.

"After a 2012 storm-related power outage at Amazon during which Netflix suffered through three hours of downtime, a Netflix engineer noted that the company had begun to work with Amazon to eliminate “single points of failure that cause region-wide outages.” They understood it was the company’s responsibility to ensure Netflix was available to entertain their customers no matter what. It would not suffice to blame their cloud provider when someone could not relax and watch a movie at the end of a long day."

https://www.networkworld.com/article/3178076/why-netflix-did...

We went multi-region as a result of the 2012 inc. source: I now manage the team responsible for performing regional evacuations (shifting traffic and scaling the savior regions).

That sounds fascinating! How often does your team have to leap into action?

We don’t usually discuss the frequency of unplanned failovers, but I will tell you that we do a planned failover at least every two weeks. The team also uses traffic shaping to perform whole system load tests with production traffic, which happens quarterly.

Do you do any chaos testing? Seems like it would slot right in, there.

I'd say yes. I heard about this tool just a week ago at a developer conference.

https://github.com/Netflix/chaosmonkey

they have invented the term, so probably yes :)

Netflix was a pioneer of chaos testing, right? https://en.m.wikipedia.org/wiki/Chaos_engineering

https://www.oreilly.com/library/view/chaos-engineering/97814... ;)

I think some Google engineers published a free Meap book on service relatability and uptime guarantees. Seemingly counterintuitive, scheduling downtime, without other teams’ prior knowledge, encourages teams to handle outages properly and reduce single points of failure, among other things.

Service Reliability Engineering is on OReilly press. It's a good book. Up there with ZeroMQ and Data Intensive Applications as maybe the best three books from OReilly in the past ten years.

Derp, Site Reliability Engineering.

https://landing.google.com/sre/books/

I think you’re misremembering about Twitter, which still doesn’t use AWS except for data analytics and cold storage last I heard (2 months ago).

Avatars were hosted on S3 for a long time, IIRC.

I am not sure if a single S3 outage pushed any big names into their own "datacenter". S3 has still the world record of reliability that you cannot challenge with your inhouse solutions. You can prove it otherwise. I would love to hear a solution that has the same durability, avabiality and scalability as S3.

For the downvoters, please just link here the proof if you disagree.

Here are the S3 numbers: https://aws.amazon.com/s3/sla/

> For the downvoters, please just link here the proof if you disagree.

https://wasabi.com/

How can they possibly guarantee eleven nines? Considering I’ve never heard of this company and they offer such crazy-sounding improvements over the big three, it feels like there should be a catch.

For data durability? I believe some AWS offerings also have an SLA of eleven 9's of data durability.

11 9s isn't uncommon. AWS S3 does 11 9s (upto 16 9s with cross region replication?) for data durability, too. AFAIK, AWS published papers about their use of formal methods to ascertain bugs from other parts of the system didn't creep in to affect durability/availability guarantees: https://blog.acolyer.org/2014/11/24/use-of-formal-methods-at...

This is a pretty neat and concise read on ObjectStorage in-use at BigTech, in case you're interested: https://maisonbisson.com/post/object-storage-prior-art-and-l...

You have to be kidding me. 14 9's is already microseconds a year. Surely below anybody's error bar for whether a service is down or not.

16 9's and aws should easily last as long as the great pyramids without a second worth of outage.

What a joke

This is for data loss. 11 9s is like 1 byte lost per terabyte-year or something, which isn't an unreasonable number.

The 16 9's are for durability, not availability. AWS is not saying S3 will never go down; they're saying it will rarely lose your data.

This number is still total bullshit. They could lose a few kb and be above that for centuries

None of the big cloud providers have unrecoverably lost hosted data yet, despite sorting vast volumes, so this doesn't seem BS to me.

AWS lost data in Australia a few years ago due to a power outage I believe.

on EBS, not on S3. EBS has much lower durability guarantees

Not losing any data yet doesn't give justification for such absurd numbers

Those numbers probably aren't as absurd as you think. 16 9s is, I think 10 bytes lost per exabyte-year of data storage.

There's perhaps the additional asterisk of "and we haven't suffered a catastrophic event that entirely puts us out of business". (Which is maybe only terrorist attacks). Because then you're talking about losing data only when cosmic-ray bitflips happen simultaneously in data centers on different continents, which I'd expect doesn't happen too often.

It's not about losing a few kb here and there.

It's about losing entire data centers to massive natural disasters once in a century.

This is why I linked the SLA page which you obviously have not read. There are different numbers for durability and availability.

11 9s of durability, barely two 9s of availability

I'm sure that's okay if you do bulk processing / time-independent analysis, but don't host production assets on wasabi.

I was asking numbers of reliability, durability and availability for a service like S3. What does wasabi has to do with that?

It's not so much AWS vs. in-house. But AWS (or GCP/DO/etc.) vs. multi/hybrid solutions. The latter of which would presumably have lower downtime.

Why would you think that self-managed has lower downtime than AWS using multiple datacenters/regions?

Multi/hybrid means you use both self managed and AWS datacenters.

Actually, I imagine that if you could go multi-regional then your self-managed solution may be directly competitive in terms of uptime. The idea that in-house can't be multi-regional is a bit old fashioned in 2019.

For several reasons, most notably: staff, build quality, standards, knowledge of building extremely reliable datacenters. Most of the people who are the most knowledgeable about datacenters also happen to be working for cloud vendors. On the top of that: software. Writing reliable software at scale is a challenge.

I don't see why multi/hybrid would have lower downtime. All cloud providers as far as I know, though I know mostly of AWS, already have their services in multiple data-centers and their endpoints in multiple regions. So if you make yourself use more then one of their AZs and Region, you would be just as multi as with your own data center.

Using a single cloud provider with a multiple region setup won't protect you from some issues in their networking infrastructure, as the subject of this thread supposedly shows.

Although I guess depending on how your own infrastructure is setup, even a multi cloud provider setup won't save you from a network outage like the current Google cloud one.

Hum, I'm not an expert on Google cloud, but for AWS, regions are completely independent and run their own networking infrastructure. So if you really wanted to tolerate a region infrastructure failure, you could design your app to fail over to another region. There shouldn't be any single point of failure between the regions, at least as far as I know.

> For the downvoters, please just link here the proof if you disagree.

> Here are the S3 numbers: https://aws.amazon.com/s3/sla/

99.9%

https://azure.microsoft.com/en-au/support/legal/sla/storage/...

99.99%

Azure is a cloud solution. The thread is about how a random datacenter with a random solution is better than S3.

Wow, he’s comparing the storages SLA of the two biggest cloud services in the world. Pedantic behavior should hurt.

>> Here are the S3 numbers: https://aws.amazon.com/s3/sla/

> 99.9%

(single-region)

There doesn't seem to be an SLA on S3-cross-region-replication configurations, but I am not aware of a multi-region S3 (read) outage, ever.

> https://azure.microsoft.com/en-au/support/legal/sla/storage/....

> 99.99%

99.99% is for "Read Access-Geo Redundant Storage (RA-GRS)"

Their equivalent SLA is the same (99.9% for "Locally Redundant Storage (LRS), Zone Redundant Storage (ZRS), and Geo Redundant Storage (GRS) Accounts.").

Cannot challenge with your own inhouse solutions, you say?

Challenge Accepted... and defeated: https://blogs.dropbox.com/tech/2016/03/magic-pocket-infrastr...

but to be fair, storage is core to Dropbox's business... this is not true for most companies.

disclaimer: I work for Dropbox, though not on Magic Pocket.

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