Observing/Alerting on influx of HTTP401's
During a recent incident: production#2203 (closed)
The exchange of CSRF tokens revealed a problem during the deployment in that users started to see HTTP401's if their CSRF token was not compatiable with a version of GitLab running. This incident revealed that we do not have any alerting to help identify this type of issue. Instead we were only notified of an issue when GitLab team members started to report a problem. Utilize this issue to determine what tooling we may be able to utilize to determine if we can create an actionable alert that will let us know that something may be wrong with a canary deployment.