Patterns for resilient architecture: Embracing failure at scale
- Build your application to be redundant, duplicating components to increase overall availability across multiple availability zones or even regions. To support this, ensure you have a stateless application and perhaps an elastic load balancer to distribute requests.
- Enable auto-scaling not just for AWS services but application auto-scaling for any service built on AWS. Determine your auto-scaling technology by the speed you tolerate - preconfigure custom golden AMIs, avoid running or configuring at startup time, replace configuration scripts with Dockerfiles, or use container platforms like ECS or Lambda functions.
- Use infrastructure as code for repeatability, knowledge sharing, and history preservation and have an immutable infrastructure with immutable components replaced for every deployment, with no updates on live systems and always starting with a new instance of every resource, with an immutable server pattern.
- As a stateless service, treat all client requests independently of prior requests and sessions, storing no information in local memory. Share state with any resources within the auto-scaling group using in-memory object caching systems or distributed databases.
Full post here, 10 mins read