goss-k8s-healthcheck

Quick and easy healthcheck for kubernetes clusters

Introduction

What is Goss?

Goss (http://goss.rocks) is a YAML based serverspec alternative tool for validating a server’s configuration. It eases the process of writing tests by allowing the user to generate tests from the current system state. Once the test suite is written they can be executed, waited-on, or served as a health endpoint.

What is goss-k8s-healthcheck?

goss-k8s-healthcheck is a starting point for deploying goss to a kubernetes cluster for running kubectl commands for inspecting a running cluster. Additionally, it exposes a small webservice that returns the healthcheck results in JSON format via the /healthz endpoint.

Usage

configuration

This repo includes a goss-configmap.yaml with a sample configuration. The image is preconfigured with goss and the deployment manifest creates a service account with a limited role for making read-only API requests. To customize the health checks, edit the configmap.

apiVersion: v1
data:
  goss.yaml: |
    command:
      kubectl cluster-info:
        exit-status: 0
        stderr: []
        timeout: 3000
      kubectl get componentstatus:
        exit-status: 0
        stderr: []
        timeout: 3000
      kubectl get nodes:
        exit-status: 0
        stderr: []
        timeout: 3000
      kubectl get pods --all-namespaces:
        exit-status: 0
        stderr: []
        timeout: 3000
kind: ConfigMap
metadata:
  name: goss-configmap
  namespace: goss

using goss-deployment

kubectl apply -f goss-deployment.yaml

This will set up the namespace, serviceaccount, role, and service for the goss healthcheck. Edit as needed to change deployment details or allow more permissions in the role.

goss service

goss-deployment.yaml contains a service definition to expose the goss service. To use this, simply call the url http://<service-IP>:<service-port>/healthz. The response is JSON formatted (this is tunable in goss-deployment.yaml)