EBS Multi-Attach

EBS Multi-Attach enables attaching a single Provisioned IOPS SSD (io1 or io2) volume to multiple instances that are in the same AZ.

Multiple Multi-Attach enabled volumes can be attached to an instance or set of instances.
Each instance to which the volume is attached has full read and write permission to the shared volume.

Multi-Attach helps achieve higher application availability in clustered Linux applications that manage concurrent write operations.

EBS Multi-Attach Considerations & Limitations

Multi-Attach is supported exclusively on Provisioned IOPS SSD volumes.
Multi-Attach enabled volumes can be attached
- to up to 16 Linux instances built on the Nitro System that are in the same AZ.
- to Windows instances, but the operating system does not recognize the data on the volume that is shared between the instances, which can result in data inconsistency.
Multi-Attach enabled volumes can be attached to one block device mapping per instance.

Multi-Attach enabled volumes are deleted on instance termination if the last attached instance is terminated and if that instance is configured to delete the volume on termination.
Multi-Attach enabled volumes can’t be created as boot volumes.
Multi-Attach can’t be enabled during instance launch using either the EC2 console or RunInstances API.

Multi-Attach enabled volumes do not support I/O fencing. I/O fencing protocols control write access in a shared storage environment to maintain data consistency
Multi-Attach can’t be enabled or disabled while the volume is attached to an instance.
Multi-Attach option is disabled by default.

AWS Certification Exam Practice Questions

Questions are collected from Internet and the answers are marked as per my knowledge and understanding (which might differ with yours).

AWS services are updated everyday and both the answers and questions might be outdated soon, so research accordingly.

AWS exam questions are not updated to keep up the pace with AWS updates, so even if the underlying feature has changed the question might not be updated

Open to further feedback, discussion and correction.