Deploy on Kubernetes

Explain steps to deploy KubeCF in any Kubernetes cluster

The intended audience of this document are developers wishing to contribute to the Kubecf project.

Here we explain how to deploy Kubecf using:

  • A generic kubernetes cluster.
  • A released cf-operator helm chart.
  • A released kubecf helm chart.

Kubernetes

In contrast to other recipes, we are not set on using a local cluster. Any Kubernetes cluster will do, assuming that the following requirements are met:

  • Presence of a default storage class (provisioner).

  • For use with a diego-based kubecf (default), a node OS with XFS support.

    • For GKE, using the option --image-type UBUNTU with the gcloud beta container command selects such an OS.

This can be any of, but not restricted to:

Note that how to deploy and tear-down such a cluster is outside of the scope of this recipe.

cf-operator

The cf-operator is the underlying generic tool to deploy a (modified) BOSH deployment like Kubecf for use.

It has to be installed in the same Kubernetes cluster that Kubecf will be deployed to.

Here we are not using development-specific dependencies like bazel, but only generic tools, i.e. kubectl and helm.

Installing and configuring Helm is the same regardless of the chosen foundation, and assuming that the cluster does not come with Helm Tiller pre-installed.

Deployment and Tear-down

helm install cf-operator \
     --namespace cfo \
     --set "global.operator.watchNamespace=kubecf" \
     https://s3.amazonaws.com/cf-operators/helm-charts/cf-operator-v0.4.2-147.gb88e4296.tgz

In the example above, version 0.4.1 of the operator was used. Look into the cf_operator section of the top-level def.bzl file to find the version of the operator validated against the current kubecf master.

Note: > The above helm install will generate many controllers spread over multiple pods inside the cfo namespace. > Most of these controllers run inside the cf-operator pod. > > The global.operator.watchNamespace=kubecf path tells the controllers to watch for CRD´s instances into the kubecf namespace. > > The cf-operator helm chart will generate the kubecf namespace during installation, and eventually one of the controllers will use a webhook to label this namespace with the cf-operator-ns key. > > If the kubecf namespace is deleted, but the operators are still running, they will no longer know which namespace to watch. This can lead to problems, so make sure you also delete the pods inside the cfo namespace, after deleting the kubecf namespace.

Note how the namespace the operator is installed into (cfo) differs from the namespace the operator is watching for deployments (kubecf).

This form of deployment enables restarting the operator because it is not affected by webhooks. It further enables the deletion of the Kubecf deployment namespace to start from scratch, without redeploying the operator itself.

Tear-down is done with a standard helm delete ... command.

Kubecf

With all the prerequisites handled by the preceding sections it is now possible to build and deploy kubecf itself.

This again uses helm and a released helm chart.

Deployment and Tear-down

helm install kubecf \
     --namespace kubecf \
     https://kubecf.s3.amazonaws.com/kubecf-v0.0.0-998b961.tgz \
     --set "system_domain=kubecf.suse.dev"

In this default deployment, kubecf is launched without Ingress, and it uses the Diego scheduler.

Tear-down is done with a standard helm delete ... command.

Access

To access the cluster after the cf-operator has completed the deployment and all pods are active invoke:

cf api --skip-ssl-validation "https://api.<domain>"

# Copy the admin cluster password.
admin_pass=$(kubectl get secret \
        --namespace kubecf var-cf-admin-password \
        -o jsonpath='{.data.password}' \
        | base64 --decode)

# Use the password from the previous step when requested.
cf auth admin "${admin_pass}"

Advanced Topics

Diego vs Eirini

Diego is the standard scheduler used by kubecf to deploy CF applications. Eirini is an alternative to Diego that follows a more Kubernetes native approach, deploying the CF apps directly to a Kubernetes namespace.

To activate this alternative, use the option --set features.eirini.enabled=true when deploying kubecf from its chart.

Ingress

By default, the cluster is exposed through its Kubernetes services.

To use the NGINX ingress instead, it is necessary to:

  • Install and configure the NGINX Ingress Controller.
  • Configure Kubecf to use the ingress controller.

This has to happen before deploying kubecf.

Installation of the NGINX Ingress Controller
helm install stable/nginx-ingress \
  --name ingress \
  --namespace ingress \
  --set "tcp.2222=kubecf/scheduler:2222" \
  --set "tcp.<services.tcp-router.port_range.start>=kubecf/tcp-router:<services.tcp-router.port_range.start>" \
  ...
  --set "tcp.<services.tcp-router.port_range.end>=kubecf/tcp-router:<services.tcp-router.port_range.end>"

The tcp.<port> option uses the NGINX TCP pass-through.

In the case of the tcp-router ports, one --set for each port is required, starting with services.tcp-router.port_range.start and ending with services.tcp-router.port_range.end. Those values are defined on the values.yaml file with default values.

Configure kubecf

Use the Helm option --set features.ingress.enabled=true when deploying kubecf.

External Database

By default, kubecf includes a single-availability database provided by the cf-mysql-release. Kubecf also exposes a way to use an external database via the Helm property features.external_database. Check the values.yaml for more details.

For local development with an external database, the bazel run //dev/external_database:deploy_mysql command will bring a mysql database up and running ready to be consumed by kubecf.

An example for the additional values to be provided to //dev/kubecf:apply:

features:
  external_database:
    enabled: true
    type: mysql
    host: kubecf-mysql.kubecf-mysql.svc
    port: 3306
    databases:
      uaa:
        name: uaa
        password: <root_password>
        username: root
      cc:
        name: cloud_controller
        password: <root_password>
        username: root
      bbs:
        name: diego
        password: <root_password>
        username: root
      routing_api:
        name: routing-api
        password: <root_password>
        username: root
      policy_server:
        name: network_policy
        password: <root_password>
        username: root
      silk_controller:
        name: network_connectivity
        password: <root_password>
        username: root
      locket:
        name: locket
        password: <root_password>
        username: root
      credhub:
        name: credhub
        password: <root_password>
        username: root
Last modified May 27, 2020: Update kubernetes-deploy.md (8d8c10d)