Six Strategies for Application Deployment

Recreate

• Version A is terminated then version B is rolled out.
• High down time
  Ramped (also known as rolling-update or incremental)
• Version B is slowly rolled out and replacing version A.
• Both new and old version exist during deployment, need to support multiple version at the same time
  Blue/Green
• Version B is released alongside version A, then the traffic is switched to version B.
  Canary
• Version B is released to a subset of users, then proceed to a full rollout.
• Usually used when low confidence on new release
  A/B testing
• Version B is released to a subset of users under specific condition.
• Requires intelligent load balancer
• Difficult to troubleshoot erros for a given session
  Shadow
• Version B receives real-world traffic alongside version A and doesn’t impact the response
• Can test system load
• Complex to set up, need to mock service