Multiple Volumes in ECS Compose pointing to same EFS Filesystem about compose-cli

[Adesoji1]

@Rfferrao87 The issue you described seems to be an architectural limitation due to the fact that in AWS, a single EFS (Elastic File System) filesystem can have multiple mount targets, but these must be in different subnets. If your compose file is trying to create two mount targets in the same subnet for the same EFS filesystem, it would indeed cause an error.

A possible solution to this could be to modify the ECS Compose conversion process to support using multiple access points on a single EFS filesystem. Each access point provides a specific directory on the filesystem and can enforce a certain POSIX user and group ID. This way, you can create a unique access point for each volume in your Docker Compose file, while still using the same mount target.

Here is the general outline of the steps you might take:

1. When converting from the Docker Compose file to CloudFormation, if multiple volumes are identified that refer to the same EFS filesystem, create a single mount target for them.

2. For each volume, create a unique EFS access point. Set the FileSystemId to your EFS filesystem ID and the Path to the specific directory for that volume.

3. Modify your Docker Compose file to mount the volume from the access point, not directly from the EFS filesystem.

[Rfferrao87]

@Adesoji1 I appreciate the idea, but I'm almost 100% sure I tried this before; problem is that Docker Compose's ECS Integration currently only supports linking to an external File System rather than an Access Point, at least as far as I'm aware. If there's another way to point directly to an Access Point I'd appreciate if you could share this method (regarding the docker-compose.yml syntax).