什么是 DevOps？

Traditional software organizations maintained a hard separation between development teams (who write code) and operations teams (who deploy and maintain infrastructure). This separation created friction: developers would 'throw code over the wall' to operations, who would then manage the complexity of deploying it to production. DevOps dissolves this separation by sharing responsibility for the full software lifecycle and using automation to make deployment a low-risk, repeatable process.

The technical core of DevOps is the CI/CD pipeline — Continuous Integration and Continuous Delivery (or Deployment). Continuous Integration means that every code change is automatically tested against a suite of automated tests before it can be merged, catching bugs early and preventing integration problems. Continuous Delivery ensures the software is always in a deployable state; Continuous Deployment goes further and automatically deploys every passing change to production. Supporting tools include infrastructure-as-code (Terraform, Ansible), containerization (Docker, Kubernetes), and cloud platforms (AWS, GCP, Azure) that enable environments to be provisioned programmatically rather than manually configured.

DevOps also encompasses monitoring, alerting, and incident response practices — the 'you build it, you run it' philosophy where development teams are responsible for the operational health of what they deploy. Key DevOps metrics include deployment frequency (how often code ships to production), lead time for changes (how long from commit to production), mean time to restore (how quickly incidents are resolved), and change failure rate (what percentage of deployments cause incidents).