<!--startmeta
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meta_yaml: "https://github.com/netdata/netdata/edit/master/src/go/plugin/go.d/collector/k8s_apiserver/metadata.yaml"
sidebar_label: "Kubernetes API Server"
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message: "DO NOT EDIT THIS FILE DIRECTLY, IT IS GENERATED BY THE COLLECTOR'S metadata.yaml FILE"
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# Kubernetes API Server


<img src="https://netdata.cloud/img/kubernetes.svg" width="150"/>


Plugin: go.d.plugin
Module: k8s_apiserver

<img src="https://img.shields.io/badge/maintained%20by-Netdata-%2300ab44" />

## Overview

This collector monitors Kubernetes API Server health, performance, and request metrics.

It collects metrics from the kube-apiserver's `/metrics` endpoint, providing insights into:
- Request rates, latencies, and error rates
- Current inflight and long-running requests
- Admission controller and webhook performance
- etcd backend health and object counts
- Controller work queue depths and latencies
- Authentication and audit events
- Go runtime and process metrics


The collector scrapes Prometheus-format metrics from the Kubernetes API Server's metrics endpoint.
Authentication is typically done using a ServiceAccount bearer token.


This collector is supported on all platforms.

This collector supports collecting metrics from multiple instances of this integration, including remote instances.

The ServiceAccount used must have permissions to access the `/metrics` endpoint.
In most clusters, this requires cluster-admin or a custom ClusterRole with metrics access.


Kubernetes API Server can be monitored further using the following other integrations:

- [Kubelet](/src/go/plugin/go.d/collector/k8s_kubelet/integrations/kubelet.md)
- [Kubeproxy](/src/go/plugin/go.d/collector/k8s_kubeproxy/integrations/kubeproxy.md)
- [Kubernetes Cluster State](/src/go/plugin/go.d/collector/k8s_state/integrations/kubernetes_cluster_state.md)
- [Kubernetes Containers](/src/collectors/cgroups.plugin/integrations/kubernetes_containers.md)
- [CoreDNS](/src/go/plugin/go.d/collector/coredns/integrations/coredns.md)

### Default Behavior

#### Auto-Detection

When running inside a Kubernetes cluster, the collector attempts to connect to
`https://kubernetes.default.svc:443/metrics` using the pod's ServiceAccount token.


#### Limits

The default configuration for this integration does not impose any limits on data collection.

#### Performance Impact

The default configuration for this integration is not expected to impose a significant performance impact on the system.

## Setup


You can configure the **k8s_apiserver** collector in two ways:

| Method                | Best for                                                                                 | How to                                                                                                                                 |
|-----------------------|------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------|
| [**UI**](#via-ui)     | Fast setup without editing files                                                         | Go to **Nodes → Configure this node → Collectors → Jobs**, search for **k8s_apiserver**, then click **+** to add a job. |
| [**File**](#via-file) | If you prefer configuring via file, or need to automate deployments (e.g., with Ansible) | Edit `go.d/k8s_apiserver.conf` and add a job.                                                                        |

:::important

UI configuration requires paid Netdata Cloud plan.

:::


### Prerequisites

#### ServiceAccount with metrics access

The Netdata pod must have a ServiceAccount with permissions to read metrics from the API server.
You can create a ClusterRole and ClusterRoleBinding for this purpose.



### Configuration

#### Options

The following options can be defined globally: update_every, autodetection_retry.


<details open><summary>Config options</summary>



| Group | Option | Description | Default | Required |
|:------|:-----|:------------|:--------|:---------:|
| **Collection** | update_every | Data collection interval (seconds). | 1 | no |
|  | autodetection_retry | Autodetection retry interval (seconds). Set 0 to disable. | 0 | no |
| **Target** | url | Target endpoint URL. | https://kubernetes.default.svc:443/metrics | yes |
|  | timeout | HTTP request timeout (seconds). | 2 | no |
| **HTTP Auth** | username | Username for Basic HTTP authentication. |  | no |
|  | password | Password for Basic HTTP authentication. |  | no |
|  | bearer_token_file | Path to a file containing a bearer token (used for `Authorization: Bearer`). | /var/run/secrets/kubernetes.io/serviceaccount/token | no |
| **TLS** | tls_skip_verify | Skip TLS certificate and hostname verification (insecure). | no | no |
|  | tls_ca | Path to CA bundle used to validate the server certificate. | /var/run/secrets/kubernetes.io/serviceaccount/ca.crt | no |
|  | tls_cert | Path to client TLS certificate (for mTLS). |  | no |
|  | tls_key | Path to client TLS private key (for mTLS). |  | no |
| **Proxy** | proxy_url | HTTP proxy URL. |  | no |
|  | proxy_username | Username for proxy Basic HTTP authentication. |  | no |
|  | proxy_password | Password for proxy Basic HTTP authentication. |  | no |
| **Request** | method | HTTP method to use. | GET | no |
|  | body | Request body (e.g., for POST/PUT). |  | no |
|  | headers | Additional HTTP headers (one per line as key: value). |  | no |
|  | not_follow_redirects | Do not follow HTTP redirects. | no | no |
|  | force_http2 | Force HTTP/2 (including h2c over TCP). | no | no |
| **Virtual Node** | vnode | Associates this data collection job with a [Virtual Node](https://learn.netdata.cloud/docs/netdata-agent/configuration/organize-systems-metrics-and-alerts#virtual-nodes). |  | no |


</details>


#### via UI

Configure the **k8s_apiserver** collector from the Netdata web interface:

1. Go to **Nodes**.
2. Select the node **where you want the k8s_apiserver data-collection job to run** and click the :gear: (**Configure this node**). That node will run the data collection.
3. The **Collectors → Jobs** view opens by default.
4. In the Search box, type _k8s_apiserver_ (or scroll the list) to locate the **k8s_apiserver** collector.
5. Click the **+** next to the **k8s_apiserver** collector to add a new job.
6. Fill in the job fields, then click **Test** to verify the configuration and **Submit** to save.
    - **Test** runs the job with the provided settings and shows whether data can be collected.
    - If it fails, an error message appears with details (for example, connection refused, timeout, or command execution errors), so you can adjust and retest.


#### via File

The configuration file name for this integration is `go.d/k8s_apiserver.conf`.

The file format is YAML. Generally, the structure is:

```yaml
update_every: 1
autodetection_retry: 0
jobs:
  - name: some_name1
  - name: some_name2
```
You can edit the configuration file using the [`edit-config`](https://github.com/netdata/netdata/blob/master/docs/netdata-agent/configuration/README.md#edit-configuration-files) script from the
Netdata [config directory](https://github.com/netdata/netdata/blob/master/docs/netdata-agent/configuration/README.md#locate-your-config-directory).

```bash
cd /etc/netdata 2>/dev/null || cd /opt/netdata/etc/netdata
sudo ./edit-config go.d/k8s_apiserver.conf
```

##### Examples

###### In-cluster (default)

Default configuration when running inside a Kubernetes cluster.

```yaml
jobs:
  - name: local
    url: https://kubernetes.default.svc:443/metrics
    bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
    tls_ca: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt

```
###### External access with kubectl proxy

Access API server metrics via kubectl proxy running on localhost.


<details open><summary>Config</summary>

```yaml
jobs:
  - name: via-proxy
    url: http://127.0.0.1:8001/metrics

```
</details>

###### Direct access with token

Direct access to API server with a bearer token.


<details open><summary>Config</summary>

```yaml
jobs:
  - name: direct
    url: https://api.example.com:6443/metrics
    bearer_token_file: /path/to/token
    tls_skip_verify: yes

```
</details>



## Alerts


The following alerts are available:

| Alert name  | On metric | Description |
|:------------|:----------|:------------|
| [ k8s_apiserver_request_errors ](https://github.com/netdata/netdata/blob/master/src/health/health.d/k8s_apiserver.conf) | k8s_apiserver.requests_by_code | high rate of API server request errors (5xx responses) |
| [ k8s_apiserver_latency ](https://github.com/netdata/netdata/blob/master/src/health/health.d/k8s_apiserver.conf) | k8s_apiserver.request_latency | API server request latency is high |



## Metrics

Metrics grouped by *scope*.

The scope defines the instance that the metric belongs to. An instance is uniquely identified by a set of labels.




### Per Kubernetes API Server instance

These metrics refer to the entire monitored API server instance.

This scope has no labels.

Metrics:

| Metric | Description | Dimensions | Unit |
|:------|:------------|:----------|:----|
| k8s_apiserver.requests_total | API Server Request Rate | requests | requests/s |
| k8s_apiserver.requests_dropped | API Server Dropped Requests | dropped | requests/s |
| k8s_apiserver.requests_by_verb | API Server Requests By Verb | a dimension per HTTP verb | requests/s |
| k8s_apiserver.requests_by_code | API Server Requests By Status Code | a dimension per HTTP status code | requests/s |
| k8s_apiserver.requests_by_resource | API Server Requests By Resource | a dimension per Kubernetes resource | requests/s |
| k8s_apiserver.request_latency | API Server Request Latency | p50, p90, p99 | milliseconds |
| k8s_apiserver.response_size | API Server Response Size | p50, p90, p99 | bytes |
| k8s_apiserver.inflight_requests | API Server Inflight Requests | mutating, read_only | requests |
| k8s_apiserver.longrunning_requests | API Server Long-Running Requests | longrunning | requests |
| k8s_apiserver.rest_client_requests_by_code | REST Client Requests By Status Code | a dimension per HTTP status code | requests/s |
| k8s_apiserver.rest_client_requests_by_method | REST Client Requests By Method | a dimension per HTTP method | requests/s |
| k8s_apiserver.rest_client_latency | REST Client Request Latency | p50, p90, p99 | milliseconds |
| k8s_apiserver.admission_step_latency | Admission Step Latency | validate, admit | milliseconds |
| k8s_apiserver.etcd_object_counts | Objects Stored In Etcd | a dimension per resource type | objects |
| k8s_apiserver.audit_events | API Server Audit Events | events, rejected | events/s |
| k8s_apiserver.authentication_requests | API Server Authenticated Requests | authenticated | requests/s |
| k8s_apiserver.goroutines | Goroutines | goroutines | goroutines |
| k8s_apiserver.threads | OS Threads | threads | threads |
| k8s_apiserver.process_memory | Process Memory | resident, virtual | bytes |
| k8s_apiserver.heap_memory | Go Heap Memory | alloc, inuse, stack | bytes |
| k8s_apiserver.gc_duration | GC Duration | min, p25, p50, p75, max | seconds |
| k8s_apiserver.open_fds | Open File Descriptors | open, max | file descriptors |
| k8s_apiserver.cpu_usage | CPU Usage | cpu | seconds/s |


### Per workqueue

These metrics refer to controller work queues.

Labels:

| Label      | Description     |
|:-----------|:----------------|
| controller | Controller name |

Metrics:

| Metric | Description | Dimensions | Unit |
|:------|:------------|:----------|:----|
| k8s_apiserver.workqueue_depth | Work Queue Depth | depth | items |
| k8s_apiserver.workqueue_latency | Work Queue Latency | p50, p90, p99 | microseconds |
| k8s_apiserver.workqueue_adds | Work Queue Adds | adds, retries | items/s |
| k8s_apiserver.workqueue_duration | Work Queue Work Duration | p50, p90, p99 | microseconds |


### Per admission controller

These metrics refer to admission controllers.

Labels:

| Label      | Description     |
|:-----------|:----------------|
| name | Admission controller name |

Metrics:

| Metric | Description | Dimensions | Unit |
|:------|:------------|:----------|:----|
| k8s_apiserver.admission_controller_latency | Admission Controller Latency | 5ms, 25ms, 100ms, 500ms, 1s, 2.5s, +Inf | events/s |


### Per admission webhook

These metrics refer to admission webhooks.

Labels:

| Label      | Description     |
|:-----------|:----------------|
| name | Webhook name |

Metrics:

| Metric | Description | Dimensions | Unit |
|:------|:------------|:----------|:----|
| k8s_apiserver.admission_webhook_latency | Admission Webhook Latency | 5ms, 25ms, 100ms, 500ms, 1s, 2.5s, +Inf | events/s |



## Troubleshooting

### Debug Mode

**Important**: Debug mode is not supported for data collection jobs created via the UI using the Dyncfg feature.

To troubleshoot issues with the `k8s_apiserver` collector, run the `go.d.plugin` with the debug option enabled. The output
should give you clues as to why the collector isn't working.

- Navigate to the `plugins.d` directory, usually at `/usr/libexec/netdata/plugins.d/`. If that's not the case on
  your system, open `netdata.conf` and look for the `plugins` setting under `[directories]`.

  ```bash
  cd /usr/libexec/netdata/plugins.d/
  ```

- Switch to the `netdata` user.

  ```bash
  sudo -u netdata -s
  ```

- Run the `go.d.plugin` to debug the collector:

  ```bash
  ./go.d.plugin -d -m k8s_apiserver
  ```

  To debug a specific job:

  ```bash
  ./go.d.plugin -d -m k8s_apiserver -j jobName
  ```

### Getting Logs

If you're encountering problems with the `k8s_apiserver` collector, follow these steps to retrieve logs and identify potential issues:

- **Run the command** specific to your system (systemd, non-systemd, or Docker container).
- **Examine the output** for any warnings or error messages that might indicate issues.  These messages should provide clues about the root cause of the problem.

#### System with systemd

Use the following command to view logs generated since the last Netdata service restart:

```bash
journalctl _SYSTEMD_INVOCATION_ID="$(systemctl show --value --property=InvocationID netdata)" --namespace=netdata --grep k8s_apiserver
```

#### System without systemd

Locate the collector log file, typically at `/var/log/netdata/collector.log`, and use `grep` to filter for collector's name:

```bash
grep k8s_apiserver /var/log/netdata/collector.log
```

**Note**: This method shows logs from all restarts. Focus on the **latest entries** for troubleshooting current issues.

#### Docker Container

If your Netdata runs in a Docker container named "netdata" (replace if different), use this command:

```bash
docker logs netdata 2>&1 | grep k8s_apiserver
```

### Connection refused

The API server may not be accessible. Check that:
1. The URL is correct
2. Network policies allow access
3. The ServiceAccount has proper RBAC permissions


### 401 Unauthorized

Authentication failed. Verify:
1. The bearer token file exists and is readable
2. The token is valid and not expired
3. The ServiceAccount has metrics access permissions


### Certificate errors

TLS verification failed. Options:
1. Provide the correct CA certificate path in `tls_ca`
2. Set `tls_skip_verify: yes` (not recommended for production)
