GCP VM Instance Status Check

Validates if a GCP Compute Engine VM instance is in Running state.

Infrastructure type

• Kubernetes

Use cases

GCP VM Instance Status Check probe helps you:

• Verify VM instances remain running during chaos experiments
• Validate instance recovery after failures or restarts
• Monitor VM health in multi-zone deployments
• Ensure compute availability during infrastructure chaos

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Overview

This probe uses the GCP CLI to query VM instance status and validates that the instance is in the 'RUNNING' state. It supports filtering by instance names or labels, making it flexible for various deployment scenarios.

Probe type

Command Probe

Prerequisites

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

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Probe properties

Command

healthchecks -name gcp-vm-instance

Comparator

Type	Criteria	Value
string	contains	[Pass]

The probe passes when the command output contains [Pass], indicating the VM instance is in the 'RUNNING' state.

Environment variables

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

Note: At least one of VM_INSTANCE_NAMES or INSTANCE_LABEL must be provided.

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Run properties

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	-

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Probe definition

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

Using instance names

probe:
  - name: "gcp-vm-instance-health-check"
    type: "cmdProbe"
    mode: "Continuous"
    cmdProbe/inputs:
      command: "healthchecks -name gcp-vm-instance"
      comparator:
        type: "string"
        criteria: "contains"
        value: "[Pass]"
      env:
        - name: VM_INSTANCE_NAMES
          value: "instance-1,instance-2,instance-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 instance labels

probe:
  - name: "gcp-vm-label-check"
    type: "cmdProbe"
    mode: "Edge"
    cmdProbe/inputs:
      command: "healthchecks -name gcp-vm-instance"
      comparator:
        type: "string"
        criteria: "contains"
        value: "[Pass]"
      env:
        - name: INSTANCE_LABEL
          value: "environment=production"
        - name: GCP_PROJECT_ID
          value: "my-project-123456"
        - name: ZONES
          value: "asia-south1-a"
    runProperties:
      timeout: 60s
      interval: 5s
      attempt: 3
      pollingInterval: 2s