Can I use EBS Multi-Attach volumes to turn on multiple EC2 instances to simultaneously access a standard file system?

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When you want to share storage across multiple EC2 instances, note that standard file systems may not be the right choice. Standard file systems like XFS, EXT3, EXT4, and NTFS aren't built to be accessed by multiple servers or EC2 instances at the same time.

Important: When you don't have coordination and control over writes, reads, locks, caches, and mounts, the risk of data corruption or loss increases significantly.

If you use standard file systems with EBS Multi-Attach, then make sure to use fencing protocols like NVMe Reservations. Fencing protocols help to prevent simultaneous access and reduce the risk of data corruption. To provide data resiliency and reliability for your production workloads, use clustered file systems.

When cluster-aware applications that run on Windows Server Failover Cluster (WSFC) use standard file systems, then you can share EBS Multi-Attach volumes with NVMe Reservations across multiple EC2 instances. The instances must be within the same Availability Zone. For more information, see How to deploy a SQL Server failover cluster with Amazon EBS Multi-Attach on Windows Server.

EBS Multi-Attach allows you to attach io1 and io2 Provisioned IOPS volumes up to 16 Nitro-based instances within the same Availability Zone, providing shared storage. For more information, see Considerations and limitations. Additionally, AWS offers managed file services such as Amazon EFS and Amazon FSx that provide data consistency and simplify management in multi-instance and Multi-AZ environments.