Comments on: Why Amazon customers might think twice about going east

By: Vittaly

Vittaly — Tue, 23 Oct 2012 21:35:23 +0000

Well, using multiple zones is not exactly free: there’s some inter-zone fee, although it’s not too high.
However all zones rely on a single control plane, so they are not exactly independent.
Also, EBS volumes need to be replicated into at least two zones. When one zone goes down, and EBS volumes in other zones sense that there’s no available replica, they all start the replication process at the same time to other zones. It’s exactly that mechanism that brought us-east-1 to its knees during the previous outage.

By: Rob

Rob — Tue, 23 Oct 2012 20:19:39 +0000

Nope. They clearly state that their services are isolated per Region. You can’t use their Elastic Load Balancers and Auto-Scaling groups across Regions. If you wanted to go across Regions, you would need a 3rd party Global Load Balancer in place. Data replication would need to be dealt with as well.

By: Barb Darrow

Barb Darrow — Tue, 23 Oct 2012 19:37:34 +0000

you’re right one AZ in ashburn

By: Barb Darrow

Barb Darrow — Tue, 23 Oct 2012 19:02:59 +0000

hm, i had read more AZs than that but i’ll go back and ck…. doln’t they also counsel you to balance across geos as well?

By: Rob

Rob — Tue, 23 Oct 2012 17:42:24 +0000

I’m pretty sure the EBS outage affected only 1 of the 4 Availability Zones in US East 1 Region. Amazon preaches cross AZ balancing and scaling which they don’t charge extra for. If your application can’t do that, then maybe you shouldn’t be using AWS in the first place.