<p>My issue is that I can not connect between our machines (master and slaves)
My connection command should be </p>

<pre><code>kubeadm join xxx:xxx:xxx:xxx:6443 --token a72x22.ofmqdjyzi7ot4l70     --discovery-token-ca-cert-hash sha256:3cfd9ddb1e655ef2172c12d914e2bb001434cc4c8a756919a7a6a9f0603e3131
</code></pre>

<p>I have been execute </p>

<pre><code>echo 1 &gt;/proc/sys/net/bridge/bridge-nf-call-iptables
echo 1 &gt;/proc/sys/net/ipv4/ip_forward
swapoff -a 
</code></pre>

<p>and I got the error</p>

<blockquote>
  <p>[kubelet-start] Downloading configuration for the kubelet from the
  "kubelet-config-1.15" ConfigMap in the kube-system namespace error
  execution phase kubelet-start: configmaps "kubelet-config-1.15" is
  forbidden: User "system:bootstrap:a61x22" can</p>
  
  <p>not get resource "configmaps" in API group "" in the namespace
  "kube-system"</p>
</blockquote>

<p>master kubectl version </p>

<pre><code>Client Version: version.Info{Major:"1", Minor:"15", GitVersion:"v1.15.0", GitCommit:"e8462b5b5dc2584fdcd18e6bcfe9f1e4d970a529", GitTreeState:"clean", BuildDate:"2019-06-19T16:40:16Z", GoVersion:"go1.12.5", Compiler:"gc", Platform:"linux/amd64"} Server Version: version.Info{Major:"1", Minor:"14", GitVersion:"v1.14.3", GitCommit:"5e53fd6bc17c0dec8434817e69b04a25d8ae0ff0", GitTreeState:"clean", BuildDate:"2019-06-06T01:36:19Z", GoVersion:"go1.12.5", Compiler:"gc", Platform:"linux/amd64"}
</code></pre>

<p>slaves kubectl version</p>

<pre><code>Client Version: version.Info{Major:"1", Minor:"15", GitVersion:"v1.15.0", GitCommit:"e8462b5b5dc2584fdcd18e6bcfe9f1e4d970a529", GitTreeState:"clean", BuildDate:"2019-06-19T16:40:16Z", GoVersion:"go1.12.5", Compiler:"gc", Platform:"linux/amd64"}
The connection to the server localhost:8080 was refused - did you specify the right host or port?
</code></pre>

<p>maybe my issue is connected to the host or port?</p>

<p>how can I solve this issue?</p>

shaharnakash
<p>Check if configmaps "kubelet-config-1.15" exists with the command below.</p>

<p>kubectl -n kube-system get configmap kubelet-config-1.15 </p>

<p>Maybe your master is at version 1.14 and your new node downloaded a kubelet version 1.15.
In that case your configmap didn't exists and you have a configmap kubelet-config-1.14.
Upgrade your master node to v 1.15 or install kubernetes v1.14 into your worker node.</p>

<p>You can see what version your nodes are with </p>

<p>kubectl get nodes </p>

<p>[root@master /]#  k get nodes</p>

<p>NAME     STATUS    ROLES    AGE   VERSION</p>

<p>master    Ready    master   32d   v1.14.0</p>

<p>node6     Ready       32d   v1.14.2</p>

<p>nodo2     Ready       32d   v1.14.2</p>
