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Example Preflight Specs

This section includes common examples of preflight check specifications. For more examples, see the Troubleshoot example repository in GitHub.

Check HTTP or HTTPS Requests from the Cluster​

The examples below use the http collector and the textAnalyze analyzer to check that an HTTP request to the Slack API at https://api.slack.com/methods/api.test made from the cluster returns a successful response of "status": 200,.

For more information, see HTTP and Regular Expression in the Troubleshoot documentation.

apiVersion: v1
kind: Secret
metadata:
  labels:
    troubleshoot.sh/kind: preflight
  name: "{{ .Release.Name }}-preflight-config"
stringData:
  preflight.yaml: |
    apiVersion: troubleshoot.sh/v1beta2
    kind: Preflight
    metadata:
      name: preflight-sample
    spec:
      collectors:
        - http:
            collectorName: slack
            get:
              url: https://api.slack.com/methods/api.test
      analyzers:
        - textAnalyze:
            checkName: Slack Accessible
            fileName: slack.json
            regex: '"status": 200,'
            outcomes:
              - pass:
                  when: "true"
                  message: "Can access the Slack API"
              - fail:
                  when: "false"
                  message: "Cannot access the Slack API. Check that the server can reach the internet and check [status.slack.com](https://status.slack.com)."

Check Kubernetes Version​

The examples below use the clusterVersion analyzer to check the version of Kubernetes running in the cluster. The clusterVersion analyzer uses data from the default clusterInfo collector. The clusterInfo collector is automatically included.

For more information, see Cluster Version and Cluster Info in the Troubleshoot documentation.

apiVersion: v1
kind: Secret
metadata:
  labels:
    troubleshoot.sh/kind: preflight
  name: "{{ .Release.Name }}-preflight-config"
stringData:
  preflight.yaml: |
    apiVersion: troubleshoot.sh/v1beta2
    kind: Preflight
    metadata:
      name: preflight-sample
    spec:
      analyzers:
        - clusterVersion:
            outcomes:
              - fail:
                  when: "< 1.25.0"
                  message: The application requires Kubernetes 1.25.0 or later, and recommends 1.28.0.
                  uri: https://www.kubernetes.io
              - warn:
                  when: "< 1.28.0"
                  message: Your cluster meets the minimum version of Kubernetes, but we recommend you update to 1.28.0 or later.
                  uri: https://kubernetes.io
              - pass:
                  message: Your cluster meets the recommended and required versions of Kubernetes.

Check Kubernetes Distribution​

The examples below use the distribution analyzer to check the Kubernetes distribution of the cluster. The distribution analyzer uses data from the default clusterInfo collector. The clusterInfo collector is automatically included.

For more information, see Cluster Info and Distribution in the Troubleshoot documentation.

apiVersion: v1
kind: Secret
metadata:
  labels:
    troubleshoot.sh/kind: preflight
  name: "{{ .Release.Name }}-preflight-config"
stringData:
  preflight.yaml: |
    apiVersion: troubleshoot.sh/v1beta2
    kind: Preflight
    metadata:
      name: preflight-sample
    spec:
      analyzers:              
        - distribution:
            checkName: Kubernetes distribution
            outcomes:
              - fail:
                  when: "== docker-desktop"
                  message: The application does not support Docker Desktop Clusters
              - fail:
                  when: "== microk8s"
                  message: The application does not support Microk8s Clusters
              - fail:
                  when: "== minikube"
                  message: The application does not support Minikube Clusters
              - pass:
                  when: "== eks"
                  message: EKS is a supported distribution
              - pass:
                  when: "== gke"
                  message: GKE is a supported distribution
              - pass:
                  when: "== aks"
                  message: AKS is a supported distribution
              - pass:
                  when: "== kurl"
                  message: KURL is a supported distribution
              - pass:
                  when: "== digitalocean"
                  message: DigitalOcean is a supported distribution
              - warn:
                  message: Unable to determine the distribution of Kubernetes

Check MySQL Version Using Template Functions​

The examples below use the mysql collector and the mysql analyzer to check the version of MySQL running in the cluster.

For more information, see Collect > MySQL and Analyze > MySQL in the Troubleshoot documentation.

This example uses Helm template functions to render the credentials and connection details for the MySQL server that were supplied by the user. Additionally, it uses Helm template functions to create a conditional statement so that the MySQL collector and analyzer are included in the preflight checks only when MySQL is deployed, as indicated by a .Values.global.mysql.enabled field evaluating to true.

For more information about using Helm template functions to access values from the values file, see Values Files.

apiVersion: v1
kind: Secret
metadata:
  labels:
    troubleshoot.sh/kind: preflight
  name: "{{ .Release.Name }}-preflight-config"
stringData:
  preflight.yaml: |
    apiVersion: troubleshoot.sh/v1beta2
    kind: Preflight
    metadata:
      name: preflight-sample
    spec:
      {{ if eq .Values.global.mysql.enabled true }}
      collectors:
        - mysql:
            collectorName: mysql
            uri: '{{ .Values.global.externalDatabase.user }}:{{ .Values.global.externalDatabase.password }}@tcp({{ .Values.global.externalDatabase.host }}:{{ .Values.global.externalDatabase.port }})/{{ .Values.global.externalDatabase.database }}?tls=false'
      {{ end }}
      analyzers:
        {{ if eq .Values.global.mysql.enabled true }}
        - mysql:
            checkName: Must be MySQL 8.x or later
            collectorName: mysql
            outcomes:
              - fail:
                  when: connected == false
                  message: Cannot connect to MySQL server
              - fail:
                  when: version < 8.x
                  message: The MySQL server must be at least version 8
              - pass:
                  message: The MySQL server is ready
        {{ end }}

Check Node Memory​

The examples below use the nodeResources analyzer to check that a required storage class is available in the nodes in the cluster. The nodeResources analyzer uses data from the default clusterResources collector. The clusterResources collector is automatically included.

For more information, see Cluster Resources and Node Resources in the Troubleshoot documentation.

apiVersion: v1
kind: Secret
metadata:
  labels:
    troubleshoot.sh/kind: preflight
  name: "{{ .Release.Name }}-preflight-config"
stringData:
  preflight.yaml: |
    apiVersion: troubleshoot.sh/v1beta2
    kind: Preflight
    metadata:
      name: preflight-sample
    spec:
      analyzers: 
        - nodeResources:
            checkName: Every node in the cluster must have at least 8 GB of memory, with 32 GB recommended
            outcomes:
              - fail:
                  when: "min(memoryCapacity) < 8Gi"
                  message: All nodes must have at least 8 GB of memory.
                  uri: https://kurl.sh/docs/install-with-kurl/system-requirements
              - warn:
                  when: "min(memoryCapacity) < 32Gi"
                  message: All nodes are recommended to have at least 32 GB of memory.
                  uri: https://kurl.sh/docs/install-with-kurl/system-requirements
              - pass:
                  message: All nodes have at least 32 GB of memory.

Check Node Storage Class Availability​

The examples below use the storageClass analyzer to check that a required storage class is available in the nodes in the cluster. The storageClass analyzer uses data from the default clusterResources collector. The clusterResources collector is automatically included.

For more information, see Cluster Resources and Node Resources in the Troubleshoot documentation.

apiVersion: v1
kind: Secret
metadata:
  labels:
    troubleshoot.sh/kind: preflight
  name: "{{ .Release.Name }}-preflight-config"
stringData:
  preflight.yaml: |
    apiVersion: troubleshoot.sh/v1beta2
    kind: Preflight
    metadata:
      name: preflight-sample
    spec:
      analyzers:
        - storageClass:
            checkName: Required storage classes
            storageClassName: "default"
            outcomes:
              - fail:
                  message: Could not find a storage class called "default".
              - pass:
                  message: A storage class called "default" is present.

Check Node Ephemeral Storage​

The examples below use the nodeResources analyzer to check the ephemeral storage available in the nodes in the cluster. The nodeResources analyzer uses data from the default clusterResources collector. The clusterResources collector is automatically included.

For more information, see Cluster Resources and Node Resources in the Troubleshoot documentation.

apiVersion: v1
kind: Secret
metadata:
  labels:
    troubleshoot.sh/kind: preflight
  name: "{{ .Release.Name }}-preflight-config"
stringData:
  preflight.yaml: |
    apiVersion: troubleshoot.sh/v1beta2
    kind: Preflight
    metadata:
      name: preflight-sample
    spec:
      analyzers:
        - nodeResources:
            checkName: Every node in the cluster must have at least 40 GB of ephemeral storage, with 100 GB recommended
            outcomes:
              - fail:
                  when: "min(ephemeralStorageCapacity) < 40Gi"
                  message: All nodes must have at least 40 GB of ephemeral storage.
                  uri: https://kurl.sh/docs/install-with-kurl/system-requirements
              - warn:
                  when: "min(ephemeralStorageCapacity) < 100Gi"
                  message: All nodes are recommended to have at least 100 GB of ephemeral storage.
                  uri: https://kurl.sh/docs/install-with-kurl/system-requirements
              - pass:
                  message: All nodes have at least 100 GB of ephemeral storage.

Check Requirements Are Met By At Least One Node​

The examples below use the nodeResources analyzer with filters to check that the requirements for memory, CPU cores, and architecture are met by at least one node in the cluster. The nodeResources analyzer uses data from the default clusterResources collector. The clusterResources collector is automatically included.

For more information, see Cluster Resources and Node Resources in the Troubleshoot documentation.

apiVersion: v1
kind: Secret
metadata:
  labels:
    troubleshoot.sh/kind: preflight
  name: "{{ .Release.Name }}-preflight-config"
stringData:
  preflight.yaml: |
    apiVersion: troubleshoot.sh/v1beta2
    kind: Preflight
    metadata:
      name: preflight-sample
    spec:
      analyzers:  
        - nodeResources:
            checkName: Node requirements
            filters:
            # Must have 1 node with 16 GB (available) memory and 5 cores (on a single node) with amd64 architecture
              allocatableMemory: 16Gi
              cpuArchitecture: amd64
              cpuCapacity: "5"
            outcomes:
              - fail:
                  when: "count() < 1"
                  message: This application requires at least 1 node with 16GB available memory and 5 cpu cores with amd64 architecture
              - pass:
                  message: This cluster has a node with enough memory and cpu cores

Check Total CPU Cores Across Nodes​

The examples below use the nodeResources analyzer to check the version of Kubernetes running in the cluster. The nodeResources analyzer uses data from the default clusterResources collector. The clusterResources collector is automatically included.

For more information, see Cluster Resources and Node Resources in the Troubleshoot documentation.

apiVersion: v1
kind: Secret
metadata:
  labels:
    troubleshoot.sh/kind: preflight
  name: "{{ .Release.Name }}-preflight-config"
stringData:
  preflight.yaml: |
    apiVersion: troubleshoot.sh/v1beta2
    kind: Preflight
    metadata:
      name: preflight-sample
    spec:
      analyzers:
        - nodeResources:
            checkName: Total CPU Cores in the cluster is 4 or greater
            outcomes:
              - fail:
                  when: "sum(cpuCapacity) < 4"
                  message: The cluster must contain at least 4 cores
                  uri: https://kurl.sh/docs/install-with-kurl/system-requirements
              - pass:
                  message: There are at least 4 cores in the cluster