its not about AWS/Azure etc. They are providing IaaS. Literally compute services littered around the globe. It is up to these so-called cloud service providers, like heroku, to utilize that infrastructure to achieve 99.999%.
I even gave a link in my comment to what AWS say about this.
Are people downvoting me because they dont read, or what?
You make it sound like AWS has 100% uptime and services built on top of them are completely to blame.
And for something like Heroku's managed DBs you can't just achieve 99.99999% availability on a DB without making certain sacrifices. Availability isn't everything past a certain point
Thats not what im doing at all. I even gave a link to AWS documentation of achieving 5-nines by utilizing multiple AZs, etc. I also reiterated this in the comment you responded to above..
What sacrifices you talking about when synchronously replicating to a backup environment? Write latency? How do you deal with that usually? How much is too much? There are strategies to deal with reducing replication related latency depending on level of consistency required.
