I recently put together a Terraform repository to manage a Kubernetes cluster deployment on DigitalOcean:
The goal of this project was to deploy a cluster, along with a workload for the DigitalOcean cloud controller (to allow Kubernetes to provision things like DO Load Balancers and Block Storage as Kubernetes resources like the service
LoadBalancer type ingress, and
Volumes using the
do-storage-class) along with facilities for scaling the node pool and storing the Terraform state in DigitalOcean Spaces object storage.
Once you clone the above repository, in a file called
terraform.tfvars, you can define different variables, but using the
terraform.tfvars.sample file as a template, you can provide the two non-optional variables:
digitalocean_token = "digitalocean_rw_api_key" ssh_key_fingerprints = ["key:fingerprint1","key:fingerprint2"]
I recommend looking at
vars.tf for a complete listing of variables available to you, however, one of new is
secrets_encrypt (defaults to
no) that, when set to
yes will configure at-rest Secrets encryption for you cluster on spin-up.
Once you have all of your options set, the remaining step before you can plan your Terraform script is to proceed to initialize your terraform provider using the Makefile:
which will prompt you for your DigitalOcean Spaces credentials, and then you can format, validate, and plan your deployment:
To scale the pool, you can modify
terraform.tfvars to the desired value, and plan and apply another run. Updating the join key will only require that you refresh (or retrieve, this result is stored in Terraform state) the join token from Terraform stored in
_b (concatenated to generate a valid token for
kubeadm, then provide to
kubeadm token create [token] to keep this in TF state, rather than local to kubeadm, and having to manually provide it to the new nodes) on the controller before bumping the node pool.
--- apiVersion: apps/v1 kind: Deployment metadata: name: nginx-deployment labels: app: nginx spec: replicas: 3 selector: matchLabels: app: nginx template: metadata: labels: app: nginx spec: containers: - name: nginx image: nginx:1.15.4 ports: - containerPort: 80 --- kind: Service apiVersion: v1 metadata: name: nginx spec: selector: app: nginx ports: - protocol: TCP port: 80 targetPort: 80 type: LoadBalancer
and if you are a user of
doctl, for example, you can see upon successfully completing the request for the above manifest, the output from
doctl compute load-balancer list will show a new load balancer object.