<p>I have 5 machines running Ubuntu 16.04.1 LTS. I want to set them up as a Kubernetes Cluster. Iḿ trying to follow this <a href="http://kubernetes.io/docs/getting-started-guides/kubeadm/" rel="nofollow noreferrer">getting started guide</a> where they're using <code>kubeadm</code>. </p>

<p>It all worked fine until step <strong>3/4 Installing a pod network</strong>. I've looked at there <a href="http://kubernetes.io/docs/admin/addons/" rel="nofollow noreferrer">addon page</a> to look for a pod network and chose the flannel overlay network. Iǘe copied the yaml file to the machine and executed:</p>

<pre><code>root@up01:/home/up# kubectl apply -f flannel.yml 
</code></pre>

<p>Which resulted in:</p>

<pre><code>configmap "kube-flannel-cfg" created
daemonset "kube-flannel-ds" created
</code></pre>

<p>So i thought that it went ok, but when I display all the pod stuff:</p>

<pre><code>root@up01:/etc/kubernetes/manifests# kubectl get pods --all-namespaces
NAMESPACE     NAME                              READY     STATUS              RESTARTS   AGE
kube-system   dummy-2088944543-d5f50            1/1       Running             0          50m
kube-system   etcd-up01                         1/1       Running             0          48m
kube-system   kube-apiserver-up01               1/1       Running             0          50m
kube-system   kube-controller-manager-up01      1/1       Running             0          49m
kube-system   kube-discovery-1769846148-jvx53   1/1       Running             0          50m
kube-system   kube-dns-2924299975-prlgf         0/4       ContainerCreating   0          49m
kube-system   kube-flannel-ds-jb1df             2/2       Running             0          32m
kube-system   kube-proxy-rtcht                  1/1       Running             0          49m
kube-system   kube-scheduler-up01               1/1       Running             0          49m
</code></pre>

<p>The problem is that the kube-dns keeps in the ContainerCreating state. I don't know what to do. </p>

<p>It is very likely that you missed this critical piece of information from the guide:</p>

<blockquote>
  <p>If you want to use flannel as the pod network, specify
  --pod-network-cidr 10.244.0.0/16 if you’re using the daemonset manifest below.</p>
</blockquote>

<p>If you omit this <code>kube-dns</code> will never leave the <code>ContainerCreating</code> STATUS.</p>

<p>Your <code>kubeadm init</code> command should be:</p>

<pre><code># kubeadm init --pod-network-cidr 10.244.0.0/16
</code></pre>

<p>and not</p>

<pre><code># kubeadm init
</code></pre>
