Читать книгу AWS Certified Solutions Architect Study Guide - Ben Piper, David Higby Clinton - Страница 64

You can attach as many Elastic Block Store (EBS) volumes to your instance as you like (although one volume can be attached to no more than a single instance at a time) and use them just as you would hard drives, flash drives, or USB drives with your physical server. And as with physical drives, the type of EBS volume you choose will have an impact on both performance and cost.

The AWS SLA guarantees the reliability of the data you store on its EBS volumes (promising at least 99.99 percent availability), so you don't have to worry about failure. When an EBS drive does fail, its data has already been duplicated and will probably be brought back online before anyone notices a problem. So, practically, the only thing that should concern you is how quickly and efficiently you can access your data.

There are currently four EBS volume types, two using SSD technologies and two using the older spinning hard drives. The performance of each volume type is measured in maximum IOPS/volume (where IOPS means input/output operations per second).