AWS Cost Optimization

--- name: aws-cost-cleanup description: "Automated cleanup of unused AWS resources to reduce costs" risk: safe source: community date_added: "2026-02-27" --- # AWS Cost Cleanup Automate the identification and removal of unused AWS resources to eliminate waste. ## When to Use This Skill Use this skill when you need to automatically clean up unused AWS resources to reduce costs and eliminate waste. ## Automated Cleanup Targets Storage - Unattached EBS volumes - Old EBS snapshots (>90 days) - Incomplete multipart S3 uploads - Old S3 versions in versioned buckets Compute - Stopped EC2 instances (>30 days) - Unused AMIs and associated snapshots - Unused Elastic IPs Networking - Unused Elastic Load Balancers - Unused NAT Gateways - Orphaned ENIs ## Cleanup Scripts ### Safe Cleanup (Dry-Run First) ``bash #!/bin/bash # cleanup-unused-ebs.sh echo "Finding unattached EBS volumes..." VOLUMES=$(aws ec2 describe-volumes \ --filters Name=status,Values=available \ --query 'Volumes[*].VolumeId' \ --output text) for vol in $VOLUMES; do echo "Would delete: $vol" # Uncomment to actually delete: # aws ec2 delete-volume --volume-id $vol done ` `bash #!/bin/bash # cleanup-old-snapshots.sh CUTOFF_DATE=$(date -d '90 days ago' --iso-8601) aws ec2 describe-snapshots --owner-ids self \ --query "Snapshots[?StartTime<='$CUTOFF_DATE'].[SnapshotId,StartTime,VolumeSize]" \ --output text | while read snap_id start_time size; do echo "Snapshot: $snap_id (Created: $start_time, Size: ${size}GB)" # Uncomment to delete: # aws ec2 delete-snapshot --snapshot-id $snap_id done ` `bash #!/bin/bash # release-unused-eips.sh aws ec2 describe-addresses \ --query 'Addresses[?AssociationId==null].[AllocationId,PublicIp]' \ --output text | while read alloc_id public_ip; do echo "Would release: $public_ip ($alloc_id)" # Uncomment to release: # aws ec2 release-address --allocation-id $alloc_id done ` ### S3 Lifecycle Automation `bash # Apply lifecycle policy to transition old objects to cheaper storage cat > lifecycle-policy.json <<EOF { "Rules": [ { "Id": "Archive old objects", "Status": "Enabled", "Transitions": [ { "Days": 90, "StorageClass": "STANDARD_IA" }, { "Days": 180, "StorageClass": "GLACIER" } ], "NoncurrentVersionExpiration": { "NoncurrentDays": 30 }, "AbortIncompleteMultipartUpload": { "DaysAfterInitiation": 7 } } ] } EOF aws s3api put-bucket-lifecycle-configuration \ --bucket my-bucket \ --lifecycle-configuration file://lifecycle-policy.json ` ## Cost Impact Calculator `python #!/usr/bin/env python3 # calculate-savings.py import boto3 from datetime import datetime, timedelta ec2 = boto3.client('ec2') # Calculate EBS volume savings volumes = ec2.describe_volumes( Filters=[{'Name': 'status', 'Values': ['available']}] ) total_size = sum(v['Size'] for v in volumes['Volumes']) monthly_cost = total_size * 0.10 # $0.10/GB-month for gp3 print(f"Unattached EBS Volumes: {len(volumes['Volumes'])}") print(f"Total Size: {total_size} GB") print(f"Monthly Savings: ${monthly_cost:.2f}") # Calculate Elastic IP savings addresses = ec2.describe_addresses() unused = [a for a in addresses['Addresses'] if 'AssociationId' not in a] eip_cost = len(unused) * 3.65 # $0.005/hour * 730 hours print(f"\nUnused Elastic IPs: {len(unused)}") print(f"Monthly Savings: ${eip_cost:.2f}") print(f"\nTotal Monthly Savings: ${monthly_cost + eip_cost:.2f}") print(f"Annual Savings: ${(monthly_cost + eip_cost) * 12:.2f}") ` ## Automated Cleanup Lambda `python import boto3 from datetime import datetime, timedelta def lambda_handler(event, context): ec2 = boto3.client('ec2') # Delete unattached volumes older than 7 days volumes = ec2.describe_volumes( Filters=[{'Name': 'status', 'Values': ['available']}] ) cutoff = datetime.now() - timedelta(days=7) deleted = 0 for vol in volumes['Volumes']: create_time = vol['CreateTime'].replace(tzinfo=None) if create_time < cutoff: try: ec2.delete_volume(VolumeId=vol['VolumeId']) deleted += 1 print(f"Deleted volume: {vol['VolumeId']}") except Exception as e: print(f"Error deleting {vol['VolumeId']}: {e}") return { 'statusCode': 200, 'body': f'Deleted {deleted} volumes' } `` ## Cleanup Workflow 1. Discovery Phase (Read-only) - Run all describe commands - Generate cost impact report - Review with team 2. Validation Phase - Verify resources are truly unused - Check for dependencies - Notify resource owners 3. Execution Phase (Dry-run first) - Run cleanup scripts with dry-run - Review proposed changes - Execute actual cleanup 4. Verification Phase - Confirm deletions