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AWS considers multiple facilities to be separate AZs in the same region. If you want multi region durability (besides us-east-1), you need cross region replication enabled (from the same FAQ you read).

"You specify a region when you create your Amazon S3 bucket. Within that region, your objects are redundantly stored on multiple devices across multiple facilities. Please refer to Regional Products and Services for details of Amazon S3 service availability by region"

Note, "within that region". Separate AZs, same geographic location.

"CRR is an Amazon S3 feature that automatically replicates data across AWS regions. With CRR, every object uploaded to an S3 bucket is automatically replicated to a destination bucket in a different AWS region that you choose. You can use CRR to provide lower-latency data access in different geographic regions. CRR can also help if you have a compliance requirement to store copies of data hundreds of miles apart."

This post http://shlomoswidler.com/2009/12/read-after-write-consistenc... has a quote from Jeff Barr at AWS indicating that us-east-1 is bicoastal, which is also why its eventually consistent, instead of immediately after a write (EDIT: it appears this constraint no longer applies to the US standard region).



I'm familiar with CRR.

I asked for sources about your "one datacenter" claim. Just because several facilities are in the same geographic region does not mean they are the same datacenter.

Just because something is bicoastal does not mean your data is replicated on both coasts. It could also mean that your data is stored on either the west or the east coast.

I would have trouble believing they store twice the data as their other regions but charge the same (actually a bit less!).


Multiple facilities != "one datacenter"


Like I asked below, do you have a citation?


"No one data center serves two availability zones" :

http://www.theregister.co.uk/2015/04/16/aws_data_centre_arch...


From your link:

"To solve latency, Amazon built Availability Zones on groups of tightly coupled data centres. Each data centre in a Zone is less than 25 microseconds away from its sibling and packs 102Tbps of networking."

25 microseconds at the speed of light (best case, through a vacuum; through fiber is significantly slower) is ~4.7 miles, and based on the quote, that is the furthest they are apart. If your buildings are within 1-2 miles of each other, they're essentially the same facility.

That is not geographically redundant.


Sure, it's not geographically redundant, but nobody in this thread claimed it was. DinkyG disputed that your "one datacenter" claim was false, which it appears to be.


[flagged]


Given that they created the account to comment in the DynamoDB thread, I'd guess they're a DynamoDB developer, but that doesn't invalidate anything they've said in this thread -- they even provided a 3rd party source.




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