Amazon EC2 – Elastic Compute Cloud
Amazon EC2 provides resizable compute capacity in the cloud. It reduces the time required to obtain and boot new server instances to minutes.
Instance Types
- General Purpose (e.g., t3, m6i) — balanced compute, memory, networking.
- Compute Optimised (e.g., c6i) — high-performance processors; batch workloads.
- Memory Optimised (e.g., r6i) — fast performance for large in-memory datasets.
- Storage Optimised (e.g., i3) — high sequential read/write access to large datasets.
Purchasing Options
- On-Demand — pay by the second, no commitments.
- Reserved Instances — 1 or 3 year commitment, up to 72% savings.
- Spot Instances — bid on unused capacity, up to 90% savings (can be interrupted).
- Savings Plans — flexible pricing model, commit to a consistent usage amount.
Amazon S3 – Simple Storage Service
Amazon S3 is object storage built to store and retrieve any amount of data from anywhere. It provides 99.999999999% (11 nines) durability.
Storage Classes
- S3 Standard — frequently accessed data; low latency.
- S3 Standard-IA — infrequent access; lower cost, retrieval fee applies.
- S3 One Zone-IA — stored in single AZ; 20% cheaper than Standard-IA.
- S3 Glacier Instant Retrieval — archived data with millisecond retrieval.
- S3 Glacier Flexible Retrieval — minutes-to-hours retrieval; very low cost.
- S3 Glacier Deep Archive — lowest cost; 12-hour retrieval; long-term archive.
Key Concepts
- Buckets — containers for objects; globally unique names.
- Objects — files plus metadata; up to 5 TB each.
- Bucket Policies & ACLs — control access at bucket and object level.
- Versioning — keep multiple variants of an object in the same bucket.
IAM, VPC, RDS & Lambda
AWS IAM – Identity and Access Management
IAM lets you manage access to AWS services and resources. Key components: Users (individual people/services), Groups (collection of users), Roles (assumed by services/users for temporary access), Policies (JSON documents defining permissions). Best practice: grant least privilege.
Amazon VPC – Virtual Private Cloud
VPC lets you provision a logically isolated section of AWS Cloud. Key components: Subnets (public/private), Route Tables, Internet Gateway (connect VPC to internet), NAT Gateway (allow private subnet instances to access internet), Security Groups (stateful instance-level firewall), Network ACLs (stateless subnet-level firewall).
Amazon RDS – Relational Database Service
Managed relational database service supporting MySQL, PostgreSQL, MariaDB, Oracle, SQL Server, and Amazon Aurora. Handles: provisioning, patching, backup, recovery, failover, and scaling.
AWS Lambda
Serverless compute — run code without provisioning or managing servers. Pay only for compute time consumed. Automatically scales. Supports Node.js, Python, Java, Go, .NET, Ruby, and custom runtimes.