Behind a corporate proxy (we've set our Jenkins instance environment to pick it up), no matter how we set the Jenkins proxy environment we're still getting a 503 HTTP error when trying to connect to the cluster. The cluster is also behind a Rancher instance, we followed this guide to connect to it: https://support.cloudbees.com/hc/en-us/articles/360034274532-How-to-integrate-Jenkins-with-Rancher?page=21.

The "test connection" button shows us green, but running a pipeline always fails.

Watching the cluster end, we don't see any pods being created. Attaching logs, with <redacted>.