Kubernetes: unable to join a remote master node

4/21/2020

Hello I am facing a kubeadm join problem on a remote server.

I want to create a multi-server, multi-node Kubernetes Cluster. I created a vagrantfile to create a master node and N workers. It works on a single server.

The master VM is a bridge Vm, to make it accessible to the other available Vms on the network.

I choose Calico as a network provider.

For the Master node this's what I've done: Using ansible :

  1. Initialize Kubeadm.

  2. Installing a network provider.

  3. Create the join command.

For Worker node:

  1. I execute the join command to join the running master.

I created successfully the cluster on one single hardware server. I am trying to create regular worker nodes on another server on the same LAN, I ping to the master successfully.

To join the Master node using the generated command.

kubeadm join 192.168.2.50:6443 --token ecqb8f.jffj0hzau45b4ro2   
--ignore-preflight-errors all  
--discovery-token-ca-cert-hash 
sha256:94a0144fe419cfb0cb70b868cd43pbd7a7bf45432b3e586713b995b111bf134b

But it showed this error:

error execution phase preflight: couldn't validate the identity of the API Server: 
could not find a JWS signature in the cluster-info ConfigMap for token ID "ecqb8f"

I am asking if there is any specific network configuration to join the remote master node.

-- Zouari.M
kubeadm
kubernetes

1 Answer

4/21/2020

It seems token is expired or removed. You can create token manually by running:

kubeadm token create --print-join-command

Use the output as join command.

-- hoque
Source: StackOverflow