aws resilient

Lambda vs SNS

  • Lambda limit has 1000 concurrency requests per AWS account per region
  • SNS: has capacity planning

CloudFront && Global Accelerator Against spike

  • CloudFront has more features: caching, edge location against spikes
  • CloudFront is best fit

ASG, min, max, desired

  • A schedule action set the min, max, desired sizes to what is specified. If we want to have exact xx instances at a time. schedule action is best fit.
  • Range number of instances: max & min
  • Exact number of instances: desired

Aurora Replica promotion mechanism

  • Promote highest priority (lowest numbered tier) Tier 1 -> xx
  • Largest replica size