ebs-volumes

ebs-volumes is a utility used to attach and detach AWS EBS volumes to / from an EC2 instance.

Tags set against the EC2 instance are used to designate the EBS volumes to use, and also whether volumes should be detached.

As the utility is run on the EC2 instance an IAM role must be applied with a policy that allows reading tags and assigning volumes.

Operations

All operations with ebs-volumes must be run on the EC2 instance you wish to attach or detach volumes from. For detailed options simply invoke ebs-volumes with no arguments to get help.

Attaching volumes

Tags are used to indicate which volumes the EC2 instance can attach. The format used is

volume_<device_name> = <volume_id>

For example

volume_/dev/sdh = vol-1234567890abcdef0

To run the attach operation

$ ./ebs-volumes attach

If the operation fails for any volume a non zero exit code is returned.

Detaching volumes

To detach volumes the tag detach_volumes must be set to true.

To run the detach operation

$ ./ebs-volumes detach

If the operation fails for any volume a non zero exit code is returned.

IAM Roles and Policy

The EC2 instance needs permission to read its own tags, and examine, attach and detach the designated volumes.

For example

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Action": [
        "ec2:DescribeTags",
        "ec2:DescribeVolumes",
        "ec2:AttachVolume",
        "ec2:DetachVolume"
      ],
      "Effect": "Allow",
      "Resource": "*"
    }
  ]
}