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Cliff Claven
Cliff Claven

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AWS Cloud Practitioner Exam - The Difficult Parts - Part 2: Planning and Costs

๐Ÿ’ฐ Cost & Usage Report โ€” The Billing Data Firehose

Think of it as a massive CSV delivered to an S3 bucket with every single charge broken down by hour, resource, tag, and account. The most granular billing data AWS produces โ€” built for analysts and BI tools.

Billing tools ranked by detail level:

Pricing Calculator  โ†’  estimate before you build (no real data)
Budgets             โ†’  set thresholds, get alerts
Cost Explorer       โ†’  charts/graphs of actual spend, up to 13 months back
Cost & Usage Report โ†’  raw data firehose, most detailed of all โฌ… this one
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๐Ÿ“‹ Exam trigger words
"detailed cost breakdown per resource" ยท "feed billing data into a BI tool" โ†’ Cost & Usage Report

The 6 Pillars

for Architects and engineers

Scenario signal Pillar One-liner
Single point of failure, outage, recovery Reliability Stay up, recover fast
Paying for unused resources, bill too high Cost Optimization Don't waste money
Manual processes, inconsistent deployments Operational Excellence Run it well and keep improving
Credentials exposed, no encryption Security Protect everything, always
Slow for distant users, wrong instance type Performance Efficiency Use the right resource for the job
Carbon footprint, energy, managed services Sustainability Minimize environmental impact

AWS Service Scope: Global vs Regional vs Zonal

Scope Examples
Global IAM, Route 53, CloudFront, WAF, STS
Regional S3, RDS, EFS, Lambda, SQS, SNS, AWS Batch
Zonal EC2 instances, EBS volumes

The trick: EC2 feels regional but it's zonal โ€” it lives in one AZ. EBS snapshots however are regional.


All 6 CAF Perspectives โ€” Complete Master Table

for Business leaders AND technical teams

Perspective Owned by Focuses on Key capabilities
Business CEO, CFO, COO Cloud investment drives business outcomes Strategy, portfolio, innovation
People CHRO, HR leaders Culture, skills, organizational change Training, workforce, change management
Governance CRO, Compliance Risk, compliance, investment decisions Portfolio management, data governance, risk
Platform CTO, Architects Architecture, infrastructure, tech standards IaC, networking, data architecture
Security CISO, Security engineers Protect everything, detect threats IAM, data protection, infrastructure protection
Operations IT Operations, Support Run and support cloud day to day Incident mgmt, performance, patch management

Exam trick: CAF is NOT just technical โ€” Business and People perspectives are tested heavily
Application Portfolio Management = Governance โ† students always put this in Operations

CAF Security Perspective Capabilities

Capability Does what
Infrastructure Protection Protects against external threats and unauthorized access
Identity and Access Management Controls who accesses what
Data Protection Encryption, data security at rest and in transit
Threat Detection Identifies existing threats
Incident Response Responds when breaches occur
Application Security Secures applications specifically

CAF Operations Perspective Capabilities

  • Observability
  • Event management (AIOps)
  • Incident and problem management
  • Change and release management
  • Performance and capacity management
  • Configuration management
  • Patch management
  • Availability and continuity management
  • Application management

Trigger: "meet SLAs" + "agreed-upon service levels" โ†’ Performance and Capacity Management

Remember: Application Portfolio Management = Governance perspective, NOT Operations


Shared Responsibility Model

Category Examples
AWS owns Physical infrastructure, host OS patching, networking hardware
Shared Configuration management, patch management (guest OS = you), awareness & training
Customer owns Guest OS, applications, data encryption, network traffic protection, Zone Security

The one-word trick: "host OS" = AWS. "Guest OS" = customer.


IAM Identities

IAM Concept CLI/Access Keys? Notes
IAM User โœ… Long-term credentials Common but not best practice
IAM Role โœ… Temporary credentials Best practice
IAM Group โŒ Collection of users only
IAM Policy โŒ Not an identity โ€” it's a permission document

Pricing Calculator vs Cost Explorer

Tool Use When
Pricing Calculator Planning/estimating before you build
Cost Explorer Analyzing actual spend after you've been running

Trusted Advisor โ€” 5 Categories (memorize exactly)

  1. Cost Optimization
  2. Security
  3. Fault Tolerance
  4. Performance
  5. Service Limits

Trap answers: "Instance Usage", "Infrastructure", "Storage Capacity" โ€” none of these are real categories.

AWS Support Plans โ€” Complete Feature Matrix

Feature Basic Business+ Enterprise
Cost Free Paid More expensive
Trusted Advisor checks Core only Full Full
Support API โŒ โœ… โœ…
Technical Account Manager (TAM) โŒ โŒ โœ…
Well-Architected Reviews โŒ โŒ โœ…
Operations Reviews โŒ โŒ โœ…
Infrastructure Event Management โŒ โœ… extra fee โœ… included
Concierge billing support โŒ โŒ โœ…
Response time (critical) None 1 hour 15 minutes
For workloads Dev/test Production Mission-critical

The rule: Business+ gets IEM for extra fee but NOT Well-Architected or Operations Reviews โ†’ those need Enterprise

Critical: If a question mentions Well-Architected Reviews OR Operations Reviews โ†’ Enterprise only

What Is Free vs What Costs Money

FREE COSTS MONEY
VPCs EC2 instances (per hour)
Subnets and route tables RDS instances (per hour)
IAM users, groups, roles, policies NAT Gateway (hourly + per GB processed)
CloudFormation Elastic IPs โ€” even attached to running instances
AWS Organizations Data transfer OUT to internet
Security Groups and NACLs Data transfer BETWEEN regions
AWS Console access Data transfer BETWEEN AZs (small fee)
Inbound data transfer to AWS EBS volumes (per GB per month)
S3 storage requests (mostly) Load balancers (per hour + LCUs)
DNS resolution within VPC Direct Connect (port hours + data transfer)
CloudWatch basic monitoring CloudWatch detailed monitoring and custom metrics

Biggest surprises:

  • Elastic IPs cost money even when properly attached โ€” AWS charges to discourage IPv4 hoarding
  • Data transfer INTO AWS is free โ€” you're never charged for uploads
  • Data transfer BETWEEN AZs in same region costs a small amount โ€” use this to justify multi-AZ design decisions
  • VPCs themselves are free โ€” you pay for what's inside them
  • CloudFormation is free โ€” you pay for resources it creates

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