> For the complete documentation index, see [llms.txt](https://developer.harness.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.harness.io/continuous-delivery/3.0/use-deployments/kubernetes/step-library/k8s-scale.md).

# Kubernetes Scale

The Kubernetes Scale step changes the number of running pods for a workload to a target count or percentage. Use it to scale up before a load event, scale down to save resources, or adjust a canary workload during a canary stage.

***

### Before you begin <a href="#before-you-begin" id="before-you-begin"></a>

Before you configure the step, make sure you have the following in place:

* **A Kubernetes service:** Go to [Kubernetes services](/continuous-delivery/3.0/use-deployments/kubernetes/kubernetes-services.md) to set up service manifests and an artifact source.
* **A Kubernetes infrastructure:** Go to [Kubernetes infrastructure](/continuous-delivery/3.0/use-deployments/kubernetes/kubernetes-infrastructure.md) to connect your cluster and namespace.
* **A Harness delegate in your target cluster:** The delegate runs deployment steps in the cluster.
* **Runtime configuration:** Every Kubernetes stage requires a `runtime` block specifying a connector and namespace. Go to [Kubernetes runtime configuration](/continuous-delivery/3.0/use-deployments/kubernetes/overview.md#kubernetes-runtime-configuration) to understand the required fields.

***

### Add the Kubernetes Scale step <a href="#add-the-kubernetes-scale-step" id="add-the-kubernetes-scale-step"></a>

To add the step:

1. In your pipeline, go to the Kubernetes stage.
2. Select **+ Add Step** in the execution section.
3. Search for **Kubernetes Scale** and select it.
4. Configure the step parameters described below.
5. Select **Apply Changes**.

***

### Configure the step <a href="#configure-the-step" id="configure-the-step"></a>

The following parameters are available on the Kubernetes Scale step.

| Parameter              | Description                                                                                                                         | Required |
| ---------------------- | ----------------------------------------------------------------------------------------------------------------------------------- | -------- |
| **Name**               | Display name for the step in the pipeline.                                                                                          | Required |
| **Workload**           | The workload to scale, in `[namespace/]Kind/Name` format. For example, `default/Deployment/my-app`.                                 | Required |
| **Instance Selection** | Whether to scale by instance count or percentage. Select **Count** or **Percentage**.                                               | Required |
| **Instances**          | The target number of pods (when Count is selected) or the percentage of current replicas to scale to (when Percentage is selected). | Required |
| **Kubeconfig Path**    | Path to the kubeconfig file, derived from the infrastructure configuration. Default: `${{infra.kube_config_path}}`.                 | Optional |
| **Namespace**          | Default namespace to use when the workload field does not include one.                                                              | Optional |
| **Release Name**       | Release name for pod label lookup. Default: `${{infra.releaseName}}`.                                                               | Optional |
| **Timeout**            | Maximum time the step can run before it is marked as failed. Default: `5m`.                                                         | Optional |

***

### Set the workload <a href="#set-the-workload" id="set-the-workload"></a>

Enter the workload in `[namespace/]Kind/Name` format:

* `default/Deployment/my-app`: scales the Deployment named `my-app` in the `default` namespace
* `Deployment/my-app`: uses the namespace configured in the **Namespace** field or derived from the infrastructure

Supported workload types are Deployment and DaemonSet. Only one workload can be specified per step.

You can use a Harness expression in the Workload field to reference a workload from a preceding step. This is useful in canary deployments where you target the canary workload by name:

```
<+stages.[Stage_Id].spec.execution.steps.[Step_Id].output.outputVariables.canaryWorkload>
```

***

### Configure instance count or percentage <a href="#configure-instance-count-or-percentage" id="configure-instance-count-or-percentage"></a>

**Count** scales the workload to the exact number of pods you enter.

**Percentage** scales to a percentage of the workload's current replica count. For example, if the workload has 10 replicas and you enter `50`, the step scales it to 5 replicas.

{% hint style="info" %}
**PERCENTAGE MUST BE A WHOLE NUMBER**

Harness does not support decimal percentages. Enter whole numbers only, for example, `50`, not `50.5`. The step fails if a decimal value is provided.
{% endhint %}

To remove all running pods without deleting the workload resource, enter `0` in the **Instances** field.

***

### YAML example <a href="#yaml-example" id="yaml-example"></a>

```yaml
- name: Kubernetes Scale
  id: k8sScaleStep
  template:
    uses: k8sScaleStep
    with:
      workload: "default/Deployment/my-app"
      instances: "2"
      instances_unit_type: "count"
```

To scale to a percentage of current replicas:

```yaml
- name: Kubernetes Scale
  id: k8sScaleStep
  template:
    uses: k8sScaleStep
    with:
      workload: "default/Deployment/my-app"
      instances: "50"
      instances_unit_type: "percentage"
```

***

### Read the step output <a href="#read-the-step-output" id="read-the-step-output"></a>

The step log shows the current replica count, the target replica count, and the result of the scale operation.

After the step runs, reference the pod list in downstream steps:

```
<+steps.[Step_Id].output.outputVariables.pods>
```

***

### Advanced settings <a href="#advanced-settings" id="advanced-settings"></a>

The following advanced settings are available on the Kubernetes Scale step.

* **Timeout duration**: Maximum time the step is allowed to run before being terminated.
* **On failure**: Define what happens if the step fails, such as retry, mark as success, or abort.
* **Strategy**: Configure a looping strategy to run this step over a list of values.
* **Conditional execution**: Run this step only when a specified condition is true.

***

### Limitations in the unified platform <a href="#limitations-in-the-unified-platform" id="limitations-in-the-unified-platform"></a>

{% hint style="warning" %}
**UNSUPPORTED FEATURES IN THE UNIFIED PLATFORM**

The following feature is available in the standard Harness Kubernetes Scale step but is not supported in the unified platform.

**Skip Steady State Check**: In the standard platform, the Scale step includes a built-in steady-state check that runs after scaling, controlled by the `skipSteadyStateCheck` flag. In the unified platform, this check is not built into the Scale step. To verify workload health after scaling, add a [Kubernetes Steady State Check](/continuous-delivery/3.0/use-deployments/kubernetes/step-library/k8s-steady-state-check.md) step after the Scale step.
{% endhint %}

***

### Next steps <a href="#next-steps" id="next-steps"></a>

* Go to [Kubernetes Steady State Check](/continuous-delivery/3.0/use-deployments/kubernetes/step-library/k8s-steady-state-check.md) to verify workload health after scaling.
* Go to [Kubernetes Apply](/continuous-delivery/3.0/use-deployments/kubernetes/step-library/k8s-apply.md) to apply manifests before scaling.
* Go to [Failure strategies](/harness-ai/use-harness-platform/pipelines/failure-handling/define-a-failure-strategy-on-stages-and-steps.md) to configure what happens when the Scale step fails.