In this guide we will create a Kubernetes cluster in Docker, using a containerized version of Talos. The cluster will consist of 3 master nodes, and 1 worker node.
Running Talos in Docker is intended to be used in CI pipelines, and local testing when you need a quick and easy cluster. Furthermore, if you are running Talos in production, it provides an excellent way for developers to develop against the same version of Talos.
The follow are requirements for running Talos in Docker:
- Docker 18.03 or greater
- a recent version of
Create the Cluster
Creating a local cluster is as simple as:
osctl cluster create
Once the above finishes successfully, your talosconfig(
~/.talos/config) will be configured to point to the new cluster.
Note: Startup times can take up to a minute before the cluster is available.
Configure the Cluster
Once the cluster is available, the pod security policies will need to be applied to allow the control plane to come up. Following that, the default CNI (flannel) configuration will be applied.
Retreive and Configure the
osctl kubeconfig > kubeconfig kubectl --kubeconfig kubeconfig config set-cluster talos_default --server https://127.0.0.1:6443
Apply a Pod Security Policy
The first thing we need to do is apply a PSP manifest:
kubectl --kubeconfig ./kubeconfig apply -f https://raw.githubusercontent.com/talos-systems/talos/master/hack/dev/manifests/psp.yaml
Note: Talos enforces the use of Pod Security Policies.
Deploy the CNI Provider
In this example we will deploy flannel, but Calico, and Cillium are known to work.
kubectl --kubeconfig ./kubeconfig apply -f https://raw.githubusercontent.com/talos-systems/talos/master/hack/dev/manifests/flannel.yaml
Finally we need to fix loop detection for Docker dns:
kubectl --kubeconfig ./kubeconfig apply -f https://raw.githubusercontent.com/talos-systems/talos/master/hack/dev/manifests/coredns.yaml
Using the Cluster
Once the cluster is available, you can make use of
kubectl to interact with the cluster.
For example, to view current running containers, run
osctl ps for a list of containers in the
system namespace, or
osctl ps -k for the
To view the logs of a container, use
osctl logs <container> or
osctl logs -k <container>.
Note: We only set up port forwarding to master-1 so other nodes will not be directly accessible.
To cleanup, run:
osctl cluster destroy