Tổng ôn 2 domain còn lại (chiếm 44% của exam):
- Domain 3: Design High-Performing Architectures (24%)
- Domain 4: Design Cost-Optimized Architectures (20%)
- gp3: general purpose, 3000 IOPS baseline (provision up to 16,000)
- io2 Block Express: highest perf (256,000 IOPS, 4 GB/s)
- st1: HDD throughput (big data, logs)
- sc1: cold HDD
- EFS: NFS Linux, multi-AZ, auto-scale
- FSx for Lustre: HPC, hundreds GB/s throughput
- FSx for Windows: SMB, AD integration
- FSx for ONTAP: multi-protocol enterprise
- FSx for OpenZFS: NFS ZFS
- Standard: hot data
- Intelligent-Tiering: unknown patterns
- Express One Zone: < 10ms latency
- Glacier tiers: archive
- Transfer Acceleration: faster global upload
- Multi-Region Access Points: global active-active
- T-family: burstable (general web)
- M-family: balanced
- C-family: compute-optimized
- R-family: memory-optimized
- G/P-family: GPU
- I-family: storage (NVMe SSD)
- Lambda: scale per request, 15-min limit
- Fargate: containers, no server mgmt
- Auto Scaling: target tracking, predictive
| Workload | Service |
|---|
| Relational OLTP | RDS, Aurora |
| Relational + read-heavy | Aurora với readers / RDS read replicas |
| NoSQL key-value | DynamoDB |
| Caching | ElastiCache (Redis), DAX |
| Analytics (OLAP) | Redshift |
| Search | OpenSearch |
| Time-series | Timestream |
| Ledger | QLDB |
- CloudFront: edge caching, global reach
- Global Accelerator: anycast static IPs, AWS backbone
- VPC Endpoints: avoid internet, lower latency
- Direct Connect: dedicated low-latency hybrid
- Transit Gateway: hub for multi-VPC
- Cluster placement group: low-latency between instances
- Edge locations: cache near users
Standard → Standard-IA (30 days) → Glacier Instant (90 days) → Deep Archive (365 days) → Delete (7 years)
- gp2 → gp3 (~20% saving)
- Delete unattached volumes
- Snapshot lifecycle (DLM)
- Snapshot Archive (90+ days)
- VPC Endpoints (no NAT)
- CloudFront (cheaper egress)
- Same-region traffic (free private IP)
- DataSync (efficient transfer)
- On-Demand: 0% off (flexible)
- Reserved Instance: up to 72% off (1-3y commit)
- Savings Plans: up to 72% off (flexible commit)
- Spot: up to 90% off (fault-tolerant)
- Dedicated Host: BYOL, compliance
- Compute Optimizer recommendations
- ARM Graviton (~20% cheaper)
- Lambda Power Tuning
- Aurora Serverless v2: pay per ACU
- DynamoDB On-Demand: no commitment
- Reserved DynamoDB capacity: for known throughput
- Right-size RDS (use Performance Insights)
- Lifecycle to Glacier for old data
- Cost Explorer: visualize + forecast
- Budgets: alerts + actions
- Cost Anomaly Detection: ML detect spikes
- CUR: detailed analysis with Athena
- Tags + Cost Allocation: track per project/team
- ALB + ASG + Aurora
- CloudFront for static + caching
- ElastiCache for session/data
- Auto-scaling based on metrics
- S3 data lake
- EMR / Glue for processing
- Redshift for warehouse
- Athena for ad-hoc
- S3 for training data
- SageMaker for training (Spot for cost)
- Lambda for inference
- DynamoDB / OpenSearch for feature store
- CloudFront / Global Accelerator
- DynamoDB Global Tables / Aurora Global
- S3 CRR / MRAP
- Route 53 latency routing
- Hot data: Standard
- Warm: Standard-IA
- Cold: Glacier
- Archive: Deep Archive
- Auto via lifecycle rules
- Baseline 24/7: Reserved 3y
- Variable: Savings Plans
- Burst peak: On-Demand
- Batch: Spot
- Compute Optimizer EC2 recommendations
- Delete idle resources (Trusted Advisor)
- Unused EBS, snapshots
- Idle Load Balancers, EIPs
- CloudFront caches → reduce origin
- ElastiCache → reduce DB queries
- DAX → reduce DynamoDB reads
- Lambda free tier 1M req/month
- DynamoDB On-Demand
- Pay-per-use cheaper than always-on
| Service | $/GB-month |
|---|
| S3 Standard | $0.023 |
| S3 Standard-IA | $0.0125 |
| S3 Glacier Instant | $0.004 |
| S3 Glacier Deep | $0.00099 |
| EBS gp3 | $0.08 |
| EBS io2 | $0.125 |
| EFS Standard | $0.30 |
| EFS One Zone-IA | $0.0133 |
| FSx Windows | $0.13 |
| FSx Lustre | $0.140 |
| Strategy | Discount | Term |
|---|
| On-Demand | 0% | — |
| Compute SP 1-year | ~30-50% | 1y |
| EC2 RI 1y NURI | ~30% | 1y |
| EC2 RI 1y AURI | ~36% | 1y |
| Compute SP 3-year | ~55-66% | 3y |
| EC2 RI 3y AURI | ~63-72% | 3y |
| Spot | Up to 90% | None |
- "Choose 2" or "Choose 3"
- Read all options carefully
- Each option must be true on its own
- Sometimes multiple options work
- Choose most cost-effective OR least operational overhead OR most secure
- gp3 > gp2 (newer, cheaper)
- HTTP API > REST API for simple (cheaper)
- Compute Savings Plans > EC2 Convertible RI (more flexible)
- OAC > OAI (newer)
- Application Migration Service > Server Migration Service (newer)
- Review Well-Architected pillars
- Memorize service limits (RDS replicas: 5, Aurora: 15, etc.)
- Practice scenario questions (timed)
- Get 7+ hours sleep
- Read carefully (2 min/question average)
- Flag uncertain → return at end
- Eliminate wrong answers first
- Trust your prep
- 720/1000 to pass (~72%)
- 50 scored + 15 unscored questions
- Don't stress single questions
- Aim 80%+ on practice → ready for real
Tiếp theo: Practice Exam 1 (65 câu)