container.training/slides/exercises/remotecluster-details.md

Exercise — Remote Cluster

• We want to control a remote cluster

• Then we want to run a copy of dockercoins on that cluster

• We want to be able to connect to an internal service

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Goal

• Be able to access e.g. hasher, rng, or webui

  (without exposing them with a NodePort or LoadBalancer service)

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Getting access to the cluster

• If you don't have kubectl on your machine, install it

• Download the kubeconfig file from the remote cluster

  (you can use scp or even copy-paste it)

• If you already have a kubeconfig file on your machine:

  • save the remote kubeconfig with another name (e.g. ~/.kube/config.remote)

  • set the KUBECONFIG environment variable to point to that file name

  • ...or use the --kubeconfig=... option with kubectl

• Check that you can access the cluster (e.g. kubectl get nodes)

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If you get an error...

⚠️ The following applies to clusters deployed with kubeadm

• If you have a cluster where the nodes are named node1, node2, etc.

• kubectl commands might show connection errors with internal IP addresses

  (e.g. 10.10... or 172.17...)

• In that case, you might need to edit the kubeconfig file:

  • find the server address

  • update it to put the external address of the first node of the cluster

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Deploying an app

• Deploy another copy of dockercoins from your local machine

• Access internal services (e.g. with kubectl port-forward)