Dennis' K8S playbook

This playbook deploys a number of things in a Kubernetes cluster.

Infrastructure: DNS + Certificates

• External DNS
• Cert-Manager

Software

• Keycloak
• Binderhub
• Apache Hadoop with Apache Knox
• Minio

Run the Ansible playbook directly

Configuration

Create a YAML file (e.g., your-settings.yaml) to select which software to instal (and override default configuration). See roles/*/defaults/main.yaml for the individual parameters.

Example:

domain: "bla.example.com"

# external dns + cert-manager (ip or hostname)
rfc2136_nameserver: "192.168.1.2"

# external dns
external_dns_enable: True
rfc2136_tsigSecret: "sdfkjasdasdfasdfsdaf...sadfsadfdss=="
rfc2136_tsigKeyname: "{{ domain }}"
rfc2136_tsigAlg: "hmac-sha512"

# cert-manager
cert_manager_enable: True
letsencrypt_email: "xx.yyr@example.com"

# binderhub + jupyterhub
binder_enable: True

Create

VARS="your-settings.yaml" ; ansible-playbook --extra-vars "@$VARS" create.yaml

Run some elements only (e.g., only keycloak): VARS="your-settings.yaml" ; ansible-playbook --extra-vars "@$VARS" --tags keycloak create.yaml

Destroy

VARS="your-settings.yaml" ; ansible-playbook --extra-vars "@$VARS" destroy.yaml

Requirements

Ansible and Python packages kubernetes and openshift are required. Run pip3 install kubernetes openshift.

Open Issues / Todos

• Use ClusterIssuer instead of namespaced Issuer
• Destroy does not check whether a component should have been installed in the first place (e.g., it tries to delete nginx ingress despite the fact that is shouldn't have been installed)
• Binder Tokens should be randomly generated
• Add option to configure a github access token in files/binderhub.yaml

GitHubRepoProvider:
		access_token: dsdfdsafasdfsdaffasdfassadfasdf7sdf

Using TCP/UDP services with Nginx Ingress

Add a UDP/TCP service using the NGINX ingress controller (cf. Ingress nginx for TCP and UDP services)

spec:
  template:
    spec:
      containers:
      - name: ingress-nginx-controller
        ports:
         - containerPort: 53
           hostPort: 53

Run

kubectl -n kube-system patch configmap nginx-udp-configmap  --patch '{"data":{"53":"default/my-service:53"}}'

kubectl -n kube-system patch deployment nginx-ingress-controller --patch "$(cat ingress-nginx-controller-patch.yaml)"

Some notes

• Ansible: Using Variables - Variable precedence: Where should I put a variable?