Fly Kubernetes Quickstart

Illustration by Annie Ruygt of a figure sailing a ship with a balloon overhead

Fly Kubernetes is in beta and not recommended for critical production usage. To report issues or provide feedback, email us at beta@fly.io.

To create a Kubernetes cluster, run:

fly ext k8s create 

This will start the provisioning process. You’ll be asked for a cluster name, the organization, and the region in which to create the cluster.

Once a cluster is provisioned, it will return a kubeconfig that can be used to connect to your cluster’s Kubernetes API server using kubectl.

For example:

apiVersion: v1 clusters: - name: fks-flyio-fksdemo cluster: certificate-authority-data: ... server: https://fks-flyio-fksdemo.flycast:6443 extensions: ... ... contexts: - context: cluster: fks-flyio-fksdemo user: default name: default current-context: default kind: Config preferences: {} users: - name: default user: ... ... 

We’re going to save the output into a file named kubeconfig and create an environment variable KUBECONFIG that points to the file:

export KUBECONFIG=/path/to/kubeconfig/file 

Our cluster is accessible over our organization’s private WireGuard network. To connect to our cluster, we need a WireGuard configuration.

Follow the Private Network VPN instructions to set up a permanent WireGuard connection to your Fly.io IPv6 private network.

From there, you can use standard YAML configuration to drive Kubernetes. Here’s a simple deployment example from the Kubernetes official documentation:

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:1.14.2 ports: - containerPort: 80 

This creates a ReplicaSet with 3 nginx pods. Using kubectl, we can apply this:

kubectl apply -f https://k8s.io/examples/controllers/nginx-deployment.yaml 
deployment.apps/nginx-deployment created 

We can see our deployment:

kubectl get deployments 
NAME READY UP-TO-DATE AVAILABLE AGE nginx-deployment 3/3 3 3 7s 

We can view the logs of all the pods in the deployment:

kubectl logs -l app=nginx 
Pulling container image registry-1.docker.io/library/nginx:1.14.2 Pulling container image registry-1.docker.io/library/nginx:1.14.2 Pulling container image registry-1.docker.io/library/nginx:1.14.2 Successfully prepared image registry-1.docker.io/library/nginx:1.14.2 (1.597714717s) Successfully prepared image registry-1.docker.io/library/nginx:1.14.2 (1.493016957s) Successfully prepared image registry-1.docker.io/library/nginx:1.14.2 (1.604003393s) Configuring firecracker Configuring firecracker Configuring firecracker ... 

What we don’t support

  • Multi-container pods (coming soon)
  • Network policies
  • Horizontal pod autoscaling
  • Gateway API
  • Daemon sets
  • EmptyDir volumes
  • Interactive pods (kubectl run --interactive --tty)

On container specs, we don’t support the following fields:

  • workingDir
  • ports
  • livenessProbe
  • readinessProbe
  • startupProbe
  • resizePolicy
  • stdin
  • stdinOnce
  • tty
  • EnvVarSource.fieldRef
  • EnvVarSource.resourceFieldRef
  • volumeDevices
  • lifecycle
  • terminationMessagePath
  • terminationMessagePolicy
  • imagePullPolicy
  • securityContext

Other caveats

Right now we don’t get logs from a single pod. If you try to get logs from a single pod, you’ll get the logs from every pod in the namespace.