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Learning path

Kill idle waste

Unattached volumes, idle endpoints, orphaned IPs and empty tables: delete what nothing uses.

9 lessons·~112 min total

Lessons in this path

  1. 1
    Cost AWS

    Delete idle VPC endpoints

    An interface VPC endpoint bills per hour per AZ even with zero traffic — a 3-AZ endpoint is ~$22/month for nothing. Find the idle ones and delete them (but never the free gateway kind).

    13 min
  2. 2
    Cost AWS

    Delete unused DynamoDB tables

    A DynamoDB table with no reads keeps billing for storage, reserved capacity, backups, and replicas — find the dead ones, archive their data, and delete them before the layers compound.

    13 min
  3. 3
    Cost AWS

    Delete unused EFS file systems

    An idle EFS file system has zero IO and zero connections — but it bills every gigabyte stored, every month, at a rate that dwarfs S3 and EBS.

    13 min
  4. 4
    Cost AWS

    Delete unused Elastic Network Interfaces

    A detached ENI isn't billed on its own — but it can hold a public IPv4 you're paying for, and it blocks the cleanup of everything attached to it. Find the true orphans and delete them safely.

    12 min
  5. 5
    Cost AWS

    Release unattached Elastic IPs

    An Elastic IP that isn't attached to anything still bills ~$3.65/month — and since 2024 even the ones in use cost money. Find the orphans and release them safely.

    11 min
  6. 6
    Cost AWS

    Delete idle ElastiCache clusters

    An ElastiCache cluster serving no traffic still bills per node-hour for its full reserved capacity — find the idle ones, take a final snapshot, and tear them down cleanly.

    13 min
  7. 7
    Cost AWS

    Delete empty CloudWatch log groups

    An empty log group costs almost nothing directly — but hundreds of them obscure what's actually logging, and most carry no retention waiting to bill silently.

    11 min
  8. 8
    Cost AWS

    Scale in over-provisioned Auto Scaling groups

    An ASG with a min capacity set high 'for safety' runs idle instances 24/7 — tie capacity to a real demand signal instead of a static guess.

    14 min
  9. 9
    Cost AWS

    Reduce SQS queue message retention

    Queues default to a long retention "just in case" — tighten it once you know the real consumer SLA.

    12 min