How do you ensure high availability and fault tolerance with IaC?

IaC (Infrastructure as Code) automates the deployment and management of infrastructure through code, ensuring continuous system availability and fault resistance. Its importance lies in eliminating human errors, enhancing consistency, and enabling efficient disaster recovery. Application scenarios include cloud-native environments such as Kubernetes cluster deployment, supporting systems with high business continuity requirements like online payment platforms.

The core includes templated resource definitions, with features such as redundant design (multiple instances across regions), automatic failover, and health check mechanisms. The principle involves orchestrating resource dependencies through IaC tools (e.g., Terraform) and triggering automatic repairs when errors occur. Practical applications implement load balancing and self-healing, such as multi-availability zone deployment in the cloud, significantly improving system elasticity and reducing downtime risks.

Implementation steps: 1. Write IaC scripts to define redundant components and backup strategies. 2. Integrate auto-scaling with health monitoring. 3. Test fault scenarios and deploy continuously. A typical scenario is handling peak traffic for e-commerce. Business value includes improving service availability to over 99.9%, reducing accident losses, and ensuring user experience.