A Debugging Journey from CoreDNS to Coreutils

Follow a technical conference talk that details a complex debugging investigation of CoreDNS pod failures in Kubernetes clusters. Dive into the troubleshooting process that began when CoreDNS pods entered crash loop backoff states following cluster deployment, triggered by unprivileged execution requirements in an updated CoreDNS image. Explore how the issue manifested only in worker nodes and specific OS distributions, leading to a deep investigation across multiple layers including Docker builds, capability management, FIPS/CGO configurations, runtime settings, and binary packaging in OVA. Learn valuable debugging techniques spanning CoreDNS binaries, containerd, runc, SELinux, AppArmor, Photon OS, and kernel interactions that are essential for developers, administrators, and cluster operators working with unprivileged pod execution.