Routing selects destinations for requests according to rules such as service version, user attributes, or traffic percentages. In microservices platforms, it supports controlled releases, resilience testing, and traffic operations without requiring application-code changes. section 4.5.3 section 4.3
Operational routing commonly supports:
- Split traffic between service versions for A/B testing, canary deployments, or progressive rollouts. section 4.5.3
- Route requests by preestablished rules, including a particular user-agent, while keeping multiple versions active. section 4.5.3
- Combine routing with retries, failover, timeouts, circuit breaking, fault injection, and mirroring to manage failure behavior. section 4.0 section 4.3
- Use Knative Route to map endpoints to one or more immutable Revisions, with traffic rules defined through a Knative Service. section 9.3.2
Progressive rollout
Deploy a corrected service version, send a small percentage of incoming traffic to it, verify its behavior, and increase the percentage until the old version can be retired. Knative expresses the same pattern with traffic entries such as 95% for a current revision and 5% for a candidate revision. section 4.5.3
