# AWS cost updates, week ending 2026-10-23: audit kit

Companion files for the blog post
[AWS Cost Updates, Week of October 23, 2026](/blog/aws-cost-updates-week-of-october-23-2026/).

| File | What it is |
| --- | --- |
| `cost-audit.sh` | Read-only AWS CLI script. Lists ALBs that front a single ECS service, Lambda functions with recursive loop detection turned off, and DynamoDB global table replicas. |
| `ecs-gateway-consolidation.drawio` | Editable draw.io source for the ALB consolidation diagram in the post. |

## Run the audit

Needs AWS CLI v2, `jq`, and bash 4 or later (macOS ships bash 3.2; `brew install bash`).

```bash
curl -O https://www.factualminds.com/examples/architecture-blog-2026/aws-cost-updates-week-of-october-23-2026/cost-audit.sh
chmod +x cost-audit.sh
REGION=us-east-1 ./cost-audit.sh
```

The IAM principal needs these read permissions: `ecs:ListClusters`, `ecs:ListServices`,
`ecs:DescribeServices`, `elasticloadbalancing:DescribeTargetGroups`, `lambda:ListFunctions`,
`lambda:GetFunctionRecursionConfig`, `dynamodb:ListTables`, `dynamodb:DescribeTable`.

## Expected output shape (illustrative numbers)

```text
Region: us-east-1

== 1. ALBs fronting ECS services ==
  orders-alb                                    ecs_target_groups=1
  ...
  ALBs serving exactly one ECS target group: 12
  Hourly charge on those ALBs: ~$197.10/month (LCUs excluded)
...
```

The dollar line multiplies the ALB count by `ALB_HOURLY` (default `0.0225`, the us-east-1
list price in October 2026) and 730 hours. Set `ALB_HOURLY` for other Regions. It excludes
LCU charges, which move with traffic rather than with ALB count.

## Diagram flow

1. Before: each ECS service has its own Application Load Balancer, so 25 services carry 25 hourly ALB charges.
2. After: Amazon ECS Gateway places up to 25 `awsvpc` services behind one shared ALB with host-based listener rules and a generated `*.ecs.<region>.on.aws` hostname per service.
3. The gateway itself has no charge. The ALB, ACM certificates, CloudWatch, and data transfer bill as usual.