Section Map
This section covers AWS serverless services from a Solutions Architect perspective: Lambda and its features, DynamoDB, API Gateway, Step Functions and Cognito. The exam tests serverless knowledge heavily.
| # | Topic | Key Concepts |
|---|---|---|
| 01 | Serverless Introduction | FaaS, no servers to manage, reference architecture, list of serverless services |
| 02 | AWS Lambda | Virtual functions, 15 minutes, up to 10 GB RAM, pricing, integrations, hands-on |
| 03 | Lambda Limits | 128 MB-10 GB memory, 900 s, 4 KB env vars, 10 GB /tmp, 250 MB uncompressed |
| 04 | Lambda Concurrency | 1000 default, reserved concurrency, throttling 429, provisioned concurrency |
| 05 | Lambda SnapStart | Snapshot on version publish, Java/Python/.NET, up to 10x |
| 06 | Lambda@Edge & CloudFront Functions | Viewer vs origin triggers, sub-millisecond, us-east-1 |
| 07 | Lambda in VPC | ENI, subnets, security group, RDS Proxy |
| 08 | RDS - Invoking Lambda & Event Notifications | DB invokes Lambda, event notifications via SNS/EventBridge |
| 09 | Amazon DynamoDB | Managed NoSQL, single-digit ms, provisioned vs on-demand capacity, 400 KB item size |
| 10 | DynamoDB Advanced Features | DAX, Streams, Kinesis Data Streams, global tables |
| 11 | Amazon API Gateway | Serverless REST APIs, integrations, features, deployment |
| 12 | AWS Step Functions | Visual workflow orchestration, human approval |
| 13 | Amazon Cognito | User pools, identity pools, temporary AWS credentials |
Key Exam Topics
- Serverless - you do not manage servers; originally FaaS with Lambda, now any managed service
- Lambda - up to 15 minutes, 10 GB RAM, more RAM also means more CPU and network
- Lambda limits - 4 KB env vars, 10 GB
/tmp, 250 MB uncompressed deployment, 1000 concurrent executions - 30 GB RAM, 30 minutes, 3 GB file -> Lambda is the wrong tool
- Reserved concurrency limits one function; the 1000 limit is shared account-wide; sync throttle gives 429
- Provisioned concurrency removes cold starts; SnapStart does it for Java, Python and .NET (free for Java only; Python and .NET are charged)
AWS update (2024-11)
SnapStart is free only for Java; Python (3.12+) and .NET (8+) are charged for snapshot caching and restores. The course said no cost for all three; the exam may still use the course figure. AWS source
- Docker images - prefer ECS or Fargate over Lambda on the exam
- CloudFront Functions - JavaScript, viewer only, under 1 ms, millions of requests per second
- Lambda@Edge - Node.js/Python, all four triggers, 5-10 s, authored in us-east-1
AWS update (2026-11)
Lambda@Edge function timeout is now 30 seconds, and memory follows the normal Lambda quotas. The course said 5-10 s. The exam may still use the course figure. AWS source
- Lambda in VPC - needed for private RDS and RDS Proxy (never public)
- RDS Proxy - pools connections, 66% faster failover, IAM auth with Secrets Manager
- RDS event notifications do not include data events; invoke Lambda from the database for that
- DynamoDB - managed NoSQL, single-digit millisecond latency, 400 KB max item, best when the schema must evolve quickly; provisioned vs on-demand capacity
- DAX - in-memory cache for DynamoDB with microsecond latency; DynamoDB Streams (24 hours) vs Kinesis Data Streams (up to 1 year); global tables for active-active multi-region
- API Gateway - serverless REST APIs with authentication, throttling, API keys, caching and versioning; fronts Lambda, HTTP backends and AWS services
- Step Functions - serverless visual workflow orchestration with error handling and human approval
- Cognito - identities for web and mobile app users outside AWS; user pools for sign-in, identity pools for temporary AWS credentials
Check yourself
Quiz