• Kubernetes 1.35: Enhanced Debugging with Versioned z-pages APIs Debugging Kubernetes control plane components can be challenging, especially when you need to quickly understand the runtime state of a component or verify its configuration. • With Kubernetes 1.35, we’re enhancing the z-pages debugging endpoints with structured, machine-parseable responses that make it easier to build tooling and automate troubleshooting workflows. • z-pages are special debugging endpoints exposed by Kubernetes control plane components. • Introduced as an alpha feature in Kubernetes 1.32, these endpoints provide runtime diagnostics for components like kube-apiserver , kube-controller-manager , kube-scheduler , kubelet and kube-proxy . • The name “z-pages” comes from the convention of using /*z paths for debugging endpoints. • Currently, Kubernetes supports two primary z-page endpoints: /statusz - Displays high-level component information including version information, start time, uptime, and available debug paths /flagz - Shows all command-line arguments and their values used to start the component (with confidential values redacted for security) These endpoints are valuable for human operators who need to quickly inspect component state, but until now, they only returned plain text output that was difficult to parse programmatically.

Article Summaries:

  • Kubernetes 1.35 introduces structured, versioned responses for its z‑page debugging endpoints (/statusz and /flagz). These endpoints, originally returning plain text, now support JSON output when the client specifies an Accept header (e.g., application/json;v=v1alpha1;g=config.k8s.io;as=Statusz). The new format is opt‑in and preserves backward compatibility, allowing existing tools to continue using the text format. The JSON payloads include component metadata, runtime details, and flag values, enabling automated health checks, monitoring, and tooling integration without manual parsing. This enhancement builds on the alpha z‑page feature introduced in 1.32, improving observability and troubleshooting for Kubernetes control plane components.

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