--- title: Kubernetes z-pages content_type: reference weight: 60 reviewers: - dashpole description: >- Provides runtime diagnostics for Kubernetes components, offering insights into component runtime status and configuration flags. --- {{< feature-state for_k8s_version="v1.36" state="beta" >}} Kubernetes core components can expose a suite of _z-endpoints_ to make it easier for users to debug their cluster and its components. These endpoints are strictly to be used for human inspection to gain real time debugging information of a component binary. In Kubernetes {{< skew currentVersion >}} these are **beta** features. ## z-pages Kubernetes v{{< skew currentVersion >}} allows you to enable _z-pages_ to help you troubleshoot problems with its core control plane components. These special debugging endpoints provide internal information about running components. For Kubernetes {{< skew currentVersion >}}, components serve the following endpoints (when enabled): - [z-pages](#z-pages) - [statusz](#statusz) - [statusz (structured)](#statusz-structured) - [flagz](#flagz) - [flagz (structured)](#flagz-structured) ### statusz Enabled using the `ComponentStatusz` [feature gate](/docs/reference/command-line-tools-reference/feature-gates#ComponentStatusz), the `/statusz` endpoint displays high level information about the component such as its Kubernetes version, emulation version, start time and more. The `/statusz` plain text response from the API server is similar to: ``` kube-apiserver statusz Warning: This endpoint is not meant to be machine parseable, has no formatting compatibility guarantees and is for debugging purposes only. Started: Wed Oct 16 21:03:43 UTC 2024 Up: 0 hr 00 min 16 sec Go version: go1.23.2 Binary version: 1.32.0-alpha.0.1484+5eeac4f21a491b-dirty Emulation version: 1.32.0-alpha.0.1484 Paths: /healthz /livez /metrics /readyz /statusz /version ``` #### statusz (structured) {{< feature-state feature_gate_name="ComponentStatusz" >}} Starting with Kubernetes v1.35, the `/statusz` endpoint supports a structured, versioned response format when requested with the appropriate `Accept` header. Without an `Accept` header, the endpoint returns the plain text response format by default. To request the structured response, use: ``` Accept: application/json;v=v1beta1;g=config.k8s.io;as=Statusz ``` {{< note >}} If you request `application/json` without specifying all required parameters (`g`, `v`, and `as`), the server will respond with `406 Not Acceptable`. {{< /note >}} Example structured response: ```json { "kind": "Statusz", "apiVersion": "config.k8s.io/v1beta1", "metadata": { "name": "kube-apiserver" }, "startTime": "2025-10-29T00:30:01Z", "uptimeSeconds": 856, "goVersion": "go1.23.2", "binaryVersion": "1.35.0", "emulationVersion": "1.35", "paths": [ "/healthz", "/livez", "/metrics", "/readyz", "/statusz", "/version" ] } ``` The `config.k8s.io/v1beta1` schema for the structured `/statusz` response is as follows: ```go // Statusz is the config.k8s.io/v1beta1 schema for the /statusz endpoint. type Statusz struct { // Kind is "Statusz". Kind string `json:"kind"` // APIVersion is the version of the object, e.g., "config.k8s.io/v1beta1". APIVersion string `json:"apiVersion"` // Standard object's metadata. // +optional Metadata metav1.ObjectMeta `json:"metadata,omitempty"` // StartTime is the time the component process was initiated. StartTime metav1.Time `json:"startTime"` // UptimeSeconds is the duration in seconds for which the component has been running continuously. UptimeSeconds int64 `json:"uptimeSeconds"` // GoVersion is the version of the Go programming language used to build the binary. // The format is not guaranteed to be consistent across different Go builds. // +optional GoVersion string `json:"goVersion,omitempty"` // BinaryVersion is the version of the component's binary. // The format is not guaranteed to be semantic versioning and may be an arbitrary string. BinaryVersion string `json:"binaryVersion"` // EmulationVersion is the Kubernetes API version which this component is emulating. // if present, formatted as "." // +optional EmulationVersion string `json:"emulationVersion,omitempty"` // MinimumCompatibilityVersion is the minimum Kubernetes API version with which the component is designed to work. // if present, formatted as "." // +optional MinimumCompatibilityVersion string `json:"minimumCompatibilityVersion,omitempty"` // Paths contains relative URLs to other essential read-only endpoints for debugging and troubleshooting. // +optional Paths []string `json:"paths,omitempty"` } ``` ### flagz Enabled using the `ComponentFlagz` [feature gate](/docs/reference/command-line-tools-reference/feature-gates#ComponentFlagz), the `/flagz` endpoint shows you the command line arguments that were used to start a component. The `/flagz` plain text response from the API server looks something like: ``` kube-apiserver flags Warning: This endpoint is not meant to be machine parseable, has no formatting compatibility guarantees and is for debugging purposes only. advertise-address=192.168.8.2 contention-profiling=false enable-priority-and-fairness=true profiling=true authorization-mode=[Node,RBAC] authorization-webhook-cache-authorized-ttl=5m0s authorization-webhook-cache-unauthorized-ttl=30s authorization-webhook-version=v1beta1 default-watch-cache-size=100 ``` #### flagz (structured) {{< feature-state feature_gate_name="ComponentFlagz" >}} Starting with Kubernetes v1.35, the `/flagz` endpoint supports a structured, versioned response format when requested with the appropriate `Accept` header. Without an `Accept` header, the endpoint returns the plain text response format by default. To request the structured response, use: ``` Accept: application/json;v=v1beta1;g=config.k8s.io;as=Flagz ``` {{< note >}} If you request `application/json` without specifying all required parameters (`g`, `v`, and `as`), the server will respond with `406 Not Acceptable`. {{< /note >}} Example structured response: ```json { "kind": "Flagz", "apiVersion": "config.k8s.io/v1beta1", "metadata": { "name": "kube-apiserver" }, "flags": { "advertise-address": "192.168.8.4", "allow-privileged": "true", "anonymous-auth": "true", "authorization-mode": "[Node,RBAC]", "enable-priority-and-fairness": "true", "profiling": "true", "default-watch-cache-size": "100" } } ``` The `config.k8s.io/v1beta1` schema for the structured `/flagz` response is as follows: ```go // Flagz is the config.k8s.io/v1beta1 schema for the /flagz endpoint. type Flagz struct { // Kind is "Flagz". Kind string `json:"kind"` // APIVersion is the version of the object, e.g., "config.k8s.io/v1beta1". APIVersion string `json:"apiVersion"` // Standard object's metadata. // +optional Metadata metav1.ObjectMeta `json:"metadata,omitempty"` // Flags contains the command-line flags and their values. // The keys are the flag names and the values are the flag values, // possibly with confidential values redacted. // +optional Flags map[string]string `json:"flags,omitempty"` } ``` {{< note >}} The structured responses for both `/statusz` and `/flagz` are beta features in v1.36. They are intended to provide machine-parseable output for debugging and introspection tools. {{< /note >}}