ZeroTierOne/doc/ext/kubernetes/ztkube.md

Kubernetes + ZeroTier

A self-authorizing Kubernetes cluster deployment over a private ZeroTier network.

This is a quick tutorial for setting up a Kubernetes deployment which can self-authorize each new replica onto your private ZeroTier network with no additional configuration needed when you scale. The Kubernetes-specific instructions and content is based on the hellonode tutorial. All of the files discussed below can be found here;

Preliminary tasks

Step 1: Go to my.zerotier.com and generate an API key. This key will be used by ZeroTier to automatically authorize new instances of your VMs to join your deployment network during replication.

Step 2: Create a new private network. Take note of the network ID, henceforth: nwid

Step 3: Follow the instructions from the hellonode tutorial and set up your development system (install Google Cloud SDK).

Construct docker container

Step 4: Create necessary files for inclusion in Dockerfile

• mkdir ztkube

Add the following files to the ztkube directory. These files will be compiled into the Docker image.

• Create an empty <nwid>.conf file to specify the private deployment network you created in Step 2:

• The CLI tool config file .zerotierCliSettings should contain your API keys to authorize new devices on your network. In this example the default controller is hosted by us at my.zerotier.com. Alternatively, you can host your own network controller but you'll need to modify the CLI config file accordingly.

{
  "configVersion": 1,
  "defaultCentral": "@my.zerotier.com",
  "defaultController": "@my.zerotier.com",
  "defaultOne": "@local",
  "things": {
    "local": {
      "auth": "XXXXXXXXXXXXXXXXXXXXXXXX",
      "type": "one",
      "url": "http://127.0.0.1:9993/"
    },
    "my.zerotier.com": {
      "auth": "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
      "type": "central",
      "url": "https://my.zerotier.com/"
    },
  }
}

• The Dockerfile will copy the ZeroTier service as well as the ZeroTier CLI to the image:

FROM node:4.4
EXPOSE 8080
COPY server.js .
COPY zerotier .
COPY zerotier-cli .
COPY entrypoint.sh .
COPY .zerotierCliSettings <settings path>?>
CMD node server.js

• The entrypoint.sh script will start the ZeroTier service in the VM, attempt to join your deployment network and automatically authorize the new VM if your network is set to private:

./zerotier 
zerotier-cli join $(NWID).conf
zerotier-cli net-auth $(NWID) $(DEVID)

Step 5: Lastly, build the image:

docker build -t gcr.io/$PROJECT_ID/hello-node .

Step 6: Push the docker image to your Container Registry

gcloud docker push gcr.io/$PROJECT_ID/hello-node:v1

Deploy!

Step 7: Create Kubernetes Cluster

gcloud config set compute/zone us-central1-a

gcloud container clusters create hello-world

gcloud container clusters get-credentials hello-world

Step 8: Create your pod

kubectl run hello-node --image=gcr.io/$PROJECT_ID/hello-node:v1 --port=8080

Step 9: Scale

kubectl scale deployment hello-node --replicas=4

Verify

Now, after a minute or so you can use zerotier-cli net-members <nwid> to show all of your VM instances on your ZeroTier deployment network. If you haven't configured your local CLI, you can simply log into my.zerotier.com, go to Networks -> nwid to check that your VMs are indeed members of your private network.