https://cacm.acm.org/magazines/2021/3/250706-a-second-conver...
https://news.ycombinator.com/item?id=26365873
[1] which you commented on, but others might not have seen.
I have a tough time taking him seriously reading this - I'm not sure if he's being intentionally ignorant or intentionally misleading.
I don't know of a single enterprise customer that doesn't have their data replicated to two datacenters, and then backed up to some other medium (tape or disk-based backup appliance) for anything business critical.
Their goal is 5-9's of UPTIME - the expectation is 100% data durability. You would get fired if you architected a solution keeping two copies of data in one datacenter.
Object storage absolutely has a place and I'm happy amazon was able to push a quasi-standard for the industry. Object storage prior to S3 was a hodge-podge of proprietary plays (EMC Centera, Bytecast, etc) and sort-of standards that nobody really used (CDMI). I just wish they did a better job of fairly representing it vs. turning every opportunity into a sales pitch spreading FUD about the alternatives.
He said:
> Most of our customers, if they have on-premises systems—if they're lucky—can store two objects in the same data center
You said:
> I don't know of a single enterprise customer that doesn't have their data replicated to two datacenters
His customers don't equal your enterprise customers. You are both right most likely.
Longtime consultant here with BCP/DR insight into 20+ large F500 companies... I think you would be seriously surprised at how common it is for even enterprise customers to not bother with multi-DC or even offsite backups. And even among the ones that do, many of the ones that are non-cloud-based are so immature at it that I would not put money on their backups being restorable if needed. And this is even more true for your “we’re a startup, we don’t have time to worry about backing up our data!” companies, which are in abundance.
For a small peak, go look at how many people were freaking out about losing their entire business due to the loss of a single OVH data center.
Of course, as a consultant I do naturally skew towards customers that need help with this stuff, so my perspective is probably biased towards the companies that are worse off in this regard. But they’re definitely out there.
You snipped out the part of the quote that answers your question.
"Most of our customers, if they have on-premises systems—if they're lucky—can store two objects in the same data center, which gives them four 9s. If they're really good, they may have two data centers and actually know how to replicate over two data centers, and that gives them five 9s. But eleven 9's, in terms of durability, is just unparalleled. And it trumps everything."
> I don't know of a single enterprise customer that doesn't have their data replicated to two datacenters...
Except, in AWS' case, each AZs (Availability Zones) is made up of upto 8 DCs (Data Centers), and each full-region has at least 3 AZs and 2 Transit Centers. Amazon S3 replicates data to 3 different AZs (which, I am guessing, is in addition to replicating it across DCs in a single AZ for 'eleven 9s').
With S3 cross-region replication durability may shoot up to 'sixteen 9s'? 100% durability, if it exists, is something the major Cloud providers are yet to offer?
ref: https://maisonbisson.com/post/object-storage-prior-art-and-l...
Replicating across two datacenters isn't "really good" though, that's considered table stakes.
>Except, in AWS' case, each AZs (Availability Zones) is made up of upto 8 DCs (Data Centers), and each full-region has at least 3 AZs and 2 Transit Centers. Amazon S3 replicates data to 3 different AZs (which, I am guessing, is in addition to replicating it across DCs in a single AZ for 'eleven 9s').
In AWS' case, the 8 DCs in an AZ are directly adjacent which isn't really useful for anything beyond metro (active/active) availability. I haven't seen a DR plan that doesn't have a hard requirement for the secondary copy of data to be outside of the metro loop/blast radius generally in a different state.