Cloud Infrastructure Design: Reliability and Cost

Cloud infrastructure design focuses on two big goals: reliability and cost. A practical plan keeps services up and fast, while staying within budget. Clear choices start with what users expect and what the service can guarantee. Use simple, repeatable patterns to reduce surprises when traffic changes or failures happen.

Start with clear goals. Define SLOs (service level objectives) and an acceptable error budget. These ideas guide what to build and when to invest in extra protection. When teams agree on these targets, architecture decisions become easier and more transparent.

Reliability patterns matter. Consider:

  • Multi-region deployment with automatic failover for critical services
  • Autoscaling or serverless options to handle load changes
  • Regular health checks and graceful degradation to avoid cascading failures
  • Durable backups and tested restore procedures

Costs should also be watched closely. Practical tips include:

  • Right-size resources and grow capacity only as needed
  • Favor managed services to reduce maintenance work and human error
  • Use reserved capacity or savings plans for steady loads
  • For non-critical tasks, explore spot or preemptible options to save money
  • Track data transfer and storage choices to avoid surprise egress or tier charges

Example: a three-tier web app with a global load balancer, stateless compute behind an autoscaler, and a multi-AZ database with read replicas. Add a CDN to reduce latency and a caching layer to ease database load. This setup improves uptime while keeping costs reasonable, even during traffic spikes.

Practical steps to start:

  • Define SLOs and an error budget
  • Pick a small set of trusted services
  • Test failure scenarios and runbooks
  • Review costs on a regular cadence
  • Document how to respond to incidents

Key Takeaways

  • Define clear SLOs and budgets to balance reliability and cost
  • Use reliable patterns like multi-region setups, autoscaling, and backups
  • Monitor, review, and adjust to keep both uptime and spend under control