10 Deploying confidently

 

In this chapter

  • explaining the two DORA metrics that measure stability: change failure rate and time to restore service
  • deploying safely by implementing a rollback strategy
  • using blue-green deployments and canary deployments to decrease the impact of bad deployments
  • using continuous deployment to achieve elite DORA metric performance

Deployment time is when the rubber hits the road for a lot of projects. When undertaken without automation or precautions, it can be a source of a lot of stress.

In this chapter, I’ll describe how to use automation to remove a lot of human burden from the deployment process and how to measure its effectiveness. I’ll also dive into “the other CD,” continuous deployment, and look at what’s required to pull it off, and what tradeoffs to weigh when deciding whether it’s a good approach for you.

Plenty of deployment woes

Plenty of Woofs, another social site popular with dog lovers, is a website that helps dog owners find compatible playdates for their dogs. They can look for other dog owners near them, filter pets by size, compatibility, and favorite games, and use the website to chat and share pictures.

DORA metrics for stability

DORA metrics at Plenty of Woofs

Deploying less frequently?

Deploying more frequently?

Daily deployments vs. outages

Steps toward increasing frequency

Fixing problems with the process

Rolling updates

Fixing a bug with a rolling update

Rollbacks