AZ (Availability Zone)
💡 Definition
An AWS Availability Zone (AZ) is one or more discrete data centers with redundant power, networking, and connectivity in an AWS Region. AZs are isolated from failures in other AZs and provide inexpensive, low-latency network connectivity to other AZs in the same Region.
🔑 Key Concepts
- Isolation: Each AZ is physically separate, with independent power, cooling, and networking.
- Interconnected: AZs in the same Region are connected with high-bandwidth, low-latency networking.
- Fault Tolerance: Designed so that a failure in one AZ (e.g., power outage) will not affect other AZs.
⚙️ How it Works
To achieve High Availability and Fault Tolerance, you typically deploy your application components across multiple AZs within a single Region. If one AZ goes down, your application can continue to run in the other AZs.
🎯 Use Cases
- High Availability: Deploying instances and databases across multiple AZs to ensure continuous operation.
- Disaster Recovery: Replicating data and resources across AZs to protect against localized failures.
💰 Pricing Model
- Data transfer between AZs within the same Region typically incurs a small charge.
📝 Exam Tips (CLF-C02)
- Each AWS Region has at least two AZs.
- AZs are physically separate but logically grouped within a Region.
- Deploying across multiple AZs is a fundamental High Availability strategy.
See Also: * Region * High Availability * Fault Tolerance