Troubleshooting AWS Elastic Beanstalk EFS Mount Error: "unknown filesystem type 'efs'"
Problem: When deploying an application to AWS Elastic Beanstalk, you might encounter the error "unknown filesystem type 'efs'" during the instance launch. This error signifies that your Elastic Beanstalk environment cannot properly access the Amazon Elastic File System (EFS) volume you've mounted.
Simplified: Imagine you have a shared drive (EFS) where your application stores its data. When you launch your application on Elastic Beanstalk, it can't find the shared drive, resulting in the "unknown filesystem type" error.
Scenario and Code:
Let's say you have a simple Node.js application that uses EFS for storage. Your Dockerrun.aws.json file might look like this:
{
"AWSEBDockerrunVersion": "1",
"volumes": [
{
"name": "efs-volume",
"host": {
"sourcePath": "/mnt/efs"
}
}
],
"containerDefinitions": [
{
"name": "myapp",
"image": "your-node-image",
"volumesFrom": [
"efs-volume"
]
}
]
}
This defines a volume named "efs-volume" and mounts it at /mnt/efs inside the container. However, you're receiving the "unknown filesystem type 'efs'" error.
Understanding the Error:
The error occurs because the Elastic Beanstalk instance needs specific software to interact with EFS volumes. This software, known as the "Amazon EFS client," is not automatically installed on every instance type.
Solutions:
-
Install the EFS Client:
- Manual Installation: The most common method is to install the EFS client manually using the
yumorapt-getpackage managers, depending on your Linux distribution. - Custom AMI: If you're using a custom Amazon Machine Image (AMI), ensure the EFS client is pre-installed. This simplifies deployment as you won't need to install it each time.
- Manual Installation: The most common method is to install the EFS client manually using the
-
Using the Elastic Beanstalk Platform:
- Platform Configuration: Elastic Beanstalk offers various platform configurations, some of which come pre-configured with the EFS client. You can explore these options in the Elastic Beanstalk console or documentation.
- Custom Platform: Create a custom platform based on a supported Elastic Beanstalk image, and include the EFS client installation steps in your configuration.
Example: Manual EFS Client Installation (using yum)
sudo yum install amazon-efs-utils
Verification:
After installing the EFS client, ensure the mount point is accessible. Check the contents of /mnt/efs using the ls command. You should see the files and directories within your EFS volume.
Additional Tips:
- Permissions: Confirm that the EFS volume has the appropriate permissions for your Elastic Beanstalk instance to access it.
- Security Groups: Make sure your security groups allow the necessary communication between your Elastic Beanstalk instance and the EFS volume.
- Mount Options: In some cases, you might need to modify the mount options for EFS, like adding the
_netdevflag.
Conclusion:
The "unknown filesystem type 'efs'" error is a common hurdle when integrating EFS with Elastic Beanstalk. By understanding the error and applying the solutions outlined above, you can ensure your application can seamlessly access your EFS volume and utilize its storage capabilities.
References:
