Jenkins is failing to start

Jenkins setup: running as Kubernetes pod (deployment) in EKS cluster. Jenkins controller pod image jenkins/jenkins:jdk17.
Kubestcl describe pod output:
Warning Unhealthy 36s (x157 over 4h35m) kubelet Startup probe failed: HTTP probe failed with statuscode: 500

Kubectl logs output:
SEVERE jenkins.InitReactorRunner$1#onTaskFailed: Failed ConfigurationAsCode.init
java.lang.IllegalArgumentException: Single entry map expected to configure a

It’s definetly not startup issue but problem with application code. Please help, thank you!

The message seems like it is telling you what failed. The configuration as code definition that has been provided is wrong. the security realm configuration has an error. You’ll need to fix that configuration error.