> 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/resilience-testing/chaos-engineering/use-chaos-engineering/probes/probe-templates/gcp/gcp-vm-disk-status-check.md).

# Gcp Vm Disk Status Check

Validates if a GCP Compute Engine persistent disk is in ready to use state.

## Infrastructure type <a href="#infrastructure-type" id="infrastructure-type"></a>

* **Kubernetes**

## Use cases <a href="#use-cases" id="use-cases"></a>

GCP VM Disk Status Check probe helps you:

* Verify persistent disks remain attached and ready during chaos experiments
* Validate disk availability after VM failures or restarts
* Monitor storage health during infrastructure chaos
* Ensure data persistence during compute disruptions

***

## Overview <a href="#overview" id="overview"></a>

This probe uses the GCP CLI to query persistent disk status and validates that the disk is in a ready-to-use state. It supports filtering by disk names or labels, making it flexible for various deployment scenarios.

### Probe type <a href="#probe-type" id="probe-type"></a>

**Command Probe**

### Prerequisites <a href="#prerequisites" id="prerequisites"></a>

* Kubernetes cluster with chaos infrastructure installed
* GCP credentials configured with appropriate IAM permissions:
  * `compute.disks.get`
  * `compute.disks.list`
* Network connectivity to GCP API endpoints
* Target persistent disks should exist in the specified zones

***

## Probe properties <a href="#probe-properties" id="probe-properties"></a>

### Command <a href="#command" id="command"></a>

```
healthchecks -name gcp-vm-disk
```

### Comparator <a href="#comparator" id="comparator"></a>

| Type   | Criteria | Value   |
| ------ | -------- | ------- |
| string | contains | \[Pass] |

The probe passes when the command output contains `[Pass]`, indicating the persistent disk is in a ready-to-use state.

### Environment variables <a href="#environment-variables" id="environment-variables"></a>

| Variable            | Description                                                                                                                                          | Required | Default |
| ------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------- | -------- | ------- |
| `DISK_VOLUME_NAMES` | Comma-separated list of persistent disk names to check (e.g., `disk-1,disk-2`). One of `DISK_VOLUME_NAMES` or `DISK_VOLUME_LABEL` must be specified. | No\*     | -       |
| `DISK_VOLUME_LABEL` | Label of the persistent disk to check (e.g., `env=production`). One of `DISK_VOLUME_NAMES` or `DISK_VOLUME_LABEL` must be specified.                 | No\*     | -       |
| `GCP_PROJECT_ID`    | GCP Project ID where the disk is located (e.g., `my-project-123456`).                                                                                | Yes      | -       |
| `ZONES`             | Comma-separated list of GCP zones where the disk is deployed (e.g., `us-central1-a,us-central1-b`).                                                  | Yes      | -       |

**Note:** At least one of `DISK_VOLUME_NAMES` or `DISK_VOLUME_LABEL` must be provided.

***

## Run properties <a href="#run-properties" id="run-properties"></a>

| Property          | Description                                                              | Type    | Default |
| ----------------- | ------------------------------------------------------------------------ | ------- | ------- |
| `timeout`         | Maximum time to wait for the probe to complete (e.g., `30s`, `1m`, `5m`) | String  | 300s    |
| `interval`        | Time between probe executions (e.g., `5s`, `30s`, `1m`)                  | String  | 10s     |
| `attempt`         | Number of retry attempts before marking the probe as failed              | Integer | 1       |
| `pollingInterval` | Time between retry attempts (e.g., `1s`, `5s`, `10s`)                    | String  | -       |
| `initialDelay`    | Initial delay before starting the probe (e.g., `0s`, `10s`, `30s`)       | String  | -       |
| `stopOnFailure`   | Stop the experiment if the probe fails                                   | Boolean | false   |
| `verbosity`       | Log verbosity level (`info`, `debug`, `trace`)                           | String  | -       |
| `retry`           | Number of times to retry the probe on failure                            | Integer | -       |

***

## Probe definition <a href="#probe-definition" id="probe-definition"></a>

You can define this probe in your chaos experiment as follows:

### Using disk names <a href="#using-disk-names" id="using-disk-names"></a>

```yaml
probe:
  - name: "gcp-disk-health-check"
    type: "cmdProbe"
    mode: "Continuous"
    cmdProbe/inputs:
      command: "healthchecks -name gcp-vm-disk"
      comparator:
        type: "string"
        criteria: "contains"
        value: "[Pass]"
      env:
        - name: DISK_VOLUME_NAMES
          value: "disk-1,disk-2,disk-3"
        - name: GCP_PROJECT_ID
          value: "my-project-123456"
        - name: ZONES
          value: "us-central1-a,us-central1-b"
    runProperties:
      timeout: 300s
      interval: 10s
      attempt: 1
      stopOnFailure: false
```

### Using disk labels <a href="#using-disk-labels" id="using-disk-labels"></a>

```yaml
probe:
  - name: "gcp-disk-label-check"
    type: "cmdProbe"
    mode: "Edge"
    cmdProbe/inputs:
      command: "healthchecks -name gcp-vm-disk"
      comparator:
        type: "string"
        criteria: "contains"
        value: "[Pass]"
      env:
        - name: DISK_VOLUME_LABEL
          value: "environment=production"
        - name: GCP_PROJECT_ID
          value: "my-project-123456"
        - name: ZONES
          value: "europe-west1-b"
    runProperties:
      timeout: 60s
      interval: 5s
      attempt: 3
      pollingInterval: 2s
```