blue-green-deploy.md

Blue-green deploy

Requires knctl v0.1.0+ and Knative 0.2.0+.

Blue-green deployments can be performed by controlling Knative route objects with knctl rollout command.

Deploy first version of your service and lock down route to point to this revision.

$ knctl deploy -s hello -i gcr.io/knative-samples/helloworld-go -e TARGET=first --managed-route=false
$ knctl rollout --route hello -p hello:latest=100%

(Note --managed-route=false flag that indicates to knctl that Knative route will be controlled via subsequent commands.)

Deploy another version of your service with a newly developed feature.

$ knctl deploy -s hello -i gcr.io/knative-samples/helloworld-go -e TARGET=second --managed-route=false

At this point route still points to the old revision. Let's roll out new version to 10% of users.

$ knctl rollout --route hello -p hello:latest=10% -p hello:previous=90%

Once appropriate metrics are verified that new version is OK, roll out remaining traffic.

$ knctl rollout --route hello -p hello:latest=100%

Tags

Each tag identifies single revision within a service. CLI uses Kubernetes labels to store tag information. Tags can be used to reference particular revision when changing traffic configuration. By default, CLI will apply two tags: latest and previous.

$ knctl revision tag --revision hello:latest -t stable
$ knctl revision list --service hello