Explanation
Why the waste happens and who it affects.
If this flag is set to `false` - often unintentionally in custom launch templates, AMIs, or older automation scripts - volumes persist after termination, resulting in orphaned storage. While detached volumes are easy to detect and clean up after the fact, proactively identifying attached volumes with `DeleteOnTermination=false` can prevent future waste before it occurs.
Billing model
The pricing dimensions that drive this cost.
EBS volumes are billed per GB-month of provisioned storage. If a volume is not automatically deleted when its EC2 instance is terminated, charges continue to accrue even if the volume is no longer in use.
How to detect
3 checks to find it in your estate.
- The volume is attached to an active EC2 instance
- The `DeleteOnTermination` flag is set to `false`
- The instance is not intended to retain persistent data on termination (e.g., ephemeral workloads or stateless apps)
How to fix
5 ways to remove the waste.
- Update the instance configuration to set `DeleteOnTermination=true` for non-persistent volumes
- Modify infrastructure-as-code templates and launch configurations to use the correct flag by default
- Establish policy controls or monitoring to flag instances with unnecessary persistent volume retention
- Periodically review long-lived instances for non-root volumes with this misconfiguration
- Educate engineering teams on the default behavior and risks of leaving the flag unset
Documentation
Vendor references for pricing and configuration.