AWS - Any way to have cross-AZ redundancy with EBS

Question

I'm looking for a redundancy solution for EBS. Ideally we would have an EBS volume in each AZ - in something similar to a master-slave configuration. Upon the failure of the primary EBS volume, all reads/writes would be directed to the secondary volume.

The volume is to store user data for the application, no OS or application files or anything like that.

The EC2 instances that will mount this volume are running centos, and I haven't looked into any sort of linux solution just quite yet. If there isn't any amazon solution, perhaps there is a linux one that you know of?

It just doesn't make sense to me to have a multi-az deployment if we are stuck with a critical EBS volume in a single AZ.

Thanks!!

Answer 1

No. Amazon EBS volumes reside only in one AZ. Snapshots are stored across AZs, but not 'live' volumes.

Your use-case sounds suitable for Amazon Elastic File System (EFS) for Linux or Amazon FSx for Windows File Server. They are shared network volumes that are replicated across AZs and can attach to multiple Amazon EC2 instances simultaneously.

I like to think of EBS like a directly-attached drive and EFS/FSx as a network drive. (Those aren't accurate descriptions, but they fit my mental model.)