What are the 3 main drivers of AWS billing?
- Compute used/requested (e.g. EC2 instance hours) | 2. Storage used/requested (e.g. S3 GB/month, EBS volume size) | 3. Network – outbound data transfer only (inbound is always free)
What are the 3 types of AWS Free Tier?
- Always Free: never expires (Lambda 1M requests/month, DynamoDB 25GB, etc.) | 2. 12 Months Free: from account creation (EC2 t2.micro 750hr/mo, S3 5GB, RDS 750hr/mo) | 3. Trials: short-term free trials for specific services
What are the general data transfer pricing rules?
Into AWS: always free. | Same AZ (between services): free. | Different AZs, same region: ~$0.01/GB. | To internet: $0.09/GB first tier (first 100GB/month free for some services). | To another region: ~$0.02/GB.
How is EC2 billed?
By the hour or second (minimum 60 seconds). Factors: instance size (vCPU, RAM), OS licensing type, features enabled, running vs stopped (small charge applies when stopped for EBS).
What are the EC2 pricing models with discounts?
On-Demand: baseline. | Reserved 1yr: ~40% off. | Reserved 3yr: ~60% off. | Savings Plans: up to 66% off. | Spot: up to 90% off. | Dedicated Instances/Hosts: premium pricing for compliance/licensing.
What are the 3 Reserved Instance types?
Standard RI: fixed instance type/size/OS, highest discount. | Convertible RI: can change instance family/size/OS, lower discount. | Scheduled RI: reserve for a specific recurring time window.
What are the RI payment options?
All Upfront (highest discount), Partial Upfront (moderate discount), No Upfront (lowest discount of the RI options).
What is a Spot Fleet?
A request for a mix of Spot and optionally On-Demand instances to meet a target capacity at the lowest cost.
What are Spot Blocks?
Reserved Spot capacity for 1-6 hours without interruption risk.
How is Lambda billed?
Requests: $0.20 per 1M requests ($0.0000002 per request). | Duration: $0.0000166667 per GB-second, billed in 1ms increments. | Free tier (permanent): 1M requests + 400,000 GB-seconds/month.
What are the RDS billing components?
Instance hours (engine, instance class, Multi-AZ doubles cost), storage GB/month (gp2/io1/magnetic), I/O requests (magnetic only), backup storage above 100% of DB size, data transfer. RDS RIs available at up to 69% discount.
What VPC components are free vs paid?
Free: VPC, subnets, route tables, Internet Gateway, security groups, NACLs, VPC Peering (creation). | Paid: NAT Gateway ($0.045/hr + $0.045/GB), Interface VPC Endpoints ($0.01/hr/AZ + $0.01/GB), VPN ($0.05/hr/connection), unattached Elastic IPs ($0.005/hr).
What is the S3 pricing model?
Per GB/month (varies by storage class), per 1,000 GET/PUT/DELETE requests, outbound data transfer per GB, data retrieval fees (Glacier). First 100GB/month outbound is free for some services.
What does CloudFront save vs direct S3 outbound?
Direct S3 to internet: $0.09/GB. CloudFront outbound: ~$0.0085/GB. Savings of ~$815/month per 10TB – use CloudFront as CDN to reduce data transfer costs significantly.
What is the DynamoDB pricing model?
On-Demand: $0.25 per million write request units, $0.05 per million read request units, $0.25 per GB/month storage. Provisioned capacity: pay for reserved read/write capacity units.
What is Consolidated Billing in AWS Organizations?
One payment method and one bill for all accounts. Volume discounts apply to combined usage. RIs and Savings Plans purchased in one account benefit the entire organisation.
What are Cost Allocation Tags?
Tags applied to resources (e.g. Key: Environment, Value: Production). Activated in Billing console to view and attribute costs by tag. Required for departmental chargebacks.
What is AWS Cost Explorer?
Visual cost analysis tool. Shows historical costs by service/region/tag/account up to 12+ months back. Forecasts costs for next 12 months. RI utilisation and coverage reports.
What is AWS Budgets?
Set custom cost, usage, or RI/Savings Plans utilisation budgets. Sends alerts when thresholds are breached. Can take automated actions (apply IAM policies or SCPs) when budgets are exceeded.
What are the 3 types of AWS Budgets?
Cost Budget (alert when costs exceed threshold), Usage Budget (alert on usage metrics), RI/SP Utilisation Budget (alert if commitments are underutilised).
What is the AWS Cost and Usage Report (CUR)?
The most granular billing data available. Line-item usage and costs. Published to an S3 bucket. Integrates with Athena and Redshift for detailed analysis.
What is the AWS Pricing Calculator?
A tool at calculator.aws to estimate costs before deploying resources. Useful when there is no historical data or for architecture planning.
What is AWS Compute Optimizer?
Analyses actual usage data and provides right-sizing recommendations for EC2, Lambda, and EBS to reduce costs and improve performance.
What are the 5 AWS Support plan tiers and prices?
Basic (free), Developer ($29+/mo), Business ($100+/mo), Enterprise On-Ramp ($5,500+/mo), Enterprise ($15,000+/mo).
