Canary is a deployment process in which a change is partially rolled out, then evaluated against the current deployment (baseline) to ensure that the new deployment is operating at least as well as the old. This evaluation is done using key metrics that are chosen when the canary is configured.
Canaries are usually run against deployments containing changes to code, but they can also be used for operational changes, including changes to configuration.
The canary process is not a substitute for other forms of testing.
Have metrics to evaluate
Your application might send performance metrics which are published and available by default. You can also install a monitoring agent to collect more comprehensive metrics, and you can instrument your code to generate further metrics for that agent. In any case, you need to have access to a set of metrics, using some telemetry provider, which Kayenta can then use to make the canary judgment.
Set up your canary environment
Before you can configure canary analysis and create canary stages for your pipelines, your Spinnaker administrator needs to enable canary for your installation.
How to make Canary work in Spinnaker—the high-level process
In Spinnaker, create one or more canary configurations.
The configuration provides the set of metrics for use in all pipeline canary stages that reference it, plus default scoring thresholds and weights—defaults that can be overridden in a canary stage
You can configure each metric flexibly, to define its scope and whether it fails when it deviates upward or down. You can also group metrics logically. (Any that you leave ungrouped are evaluated, but they don’t contribute to the success or failure of the canary run.)
You can think of this configuration as a templated set of queries against your metric store.
In any deployment pipeline that will use canary, add one or more canary stages.
The canary stage includes information that scopes the templated query (canary config) to a specified set of resources and time boundaries.
See also: The Canary Judge—how does it work?