title: Kubernetes does not start after restart system (Ubuntu)
body: <p>I installed K8s on my two Ubuntus in VirtualBox (Master and Node01). After installation (I proceeded according K8s doc site) I typed <code>kubectl get nodes</code> and got bot servers in status <em>Ready</em>. But after restart systems I got this: </p>
  
  <pre><code># kubectl get nodes 
  The connection to the server localhost:8080 was refused - did you specify the 
  right host or port? 
  </code></pre>
  
  <p>I checked kubelet service and it is running: </p>
  
  <pre><code># systemctl status kubelet
  kubelet.service - kubelet: The Kubernetes Node Agent 
     Loaded: loaded (/lib/systemd/system/kubelet.service; enabled; vendor preset: enabled) 
    Drop-In: /etc/systemd/system/kubelet.service.d 
             └─10-kubeadm.conf 
     Active: active (running) since Mon 2017-04-24 10:01:51 CEST; 15min ago 
       Docs: http://kubernetes.io/docs/ 
  Main PID: 13128 (kubelet) 
      Tasks: 21 
     Memory: 48.2M 
        CPU: 58.014s 
     CGroup: /system.slice/kubelet.service 
             ├─13128 /usr/bin/kubelet --kubeconfig=/etc/kubernetes/kubelet.conf --require-kubeconfig=true --pod-manifest-path=/etc/kubernetes/manifests --allow-privileged=true --cluster-dns=10.96.0.10 --cluster-domain=cluster.local 
             └─13164 journalctl -k -f 
  
  Apr 24 10:16:40 master kubelet[13128]: I0424 10:16:40.204156   13128 kuberuntime_manager.go:752] Back-off 5m0s restarting failed container=weave pod=weave-net-5qgvz_kube-system(4b7bb2f0-2691-11e7-bfb6-080027229776) 
  Apr 24 10:16:40 master kubelet[13128]: E0424 10:16:40.204694   13128 pod_workers.go:182] Error syncing pod 4b7bb2f0-2691-11e7-bfb6-080027229776 ("weave-net-5qgvz_kube-system(4b7bb2f0-2691-11e7-bfb6-080027229776)"), skipping: fail 
  Apr 24 10:16:42 master kubelet[13128]: I0424 10:16:42.972302   13128 operation_generator.go:597] MountVolume.SetUp succeeded for volume "kubernetes.io/secret/2b59d0d9-2692-11e7-bfb6-080027229776-default-token-h3v7c" (spec.Name: " 
  Apr 24 10:16:48 master kubelet[13128]: I0424 10:16:48.949731   13128 operation_generator.go:597] MountVolume.SetUp succeeded for volume "kubernetes.io/secret/2bb42bc1-2692-11e7-bfb6-080027229776-default-token-h3v7c" (spec.Name: " 
  Apr 24 10:16:51 master kubelet[13128]: I0424 10:16:51.978663   13128 operation_generator.go:597] MountVolume.SetUp succeeded for volume "kubernetes.io/secret/2b023c31-2692-11e7-bfb6-080027229776-default-token-h3v7c" (spec.Name: " 
  Apr 24 10:16:52 master kubelet[13128]: I0424 10:16:52.909589   13128 operation_generator.go:597] MountVolume.SetUp succeeded for volume "kubernetes.io/secret/4b7bb2f0-2691-11e7-bfb6-080027229776-default-token-gslqd" (spec.Name: " 
  Apr 24 10:16:53 master kubelet[13128]: I0424 10:16:53.186057   13128 kuberuntime_manager.go:458] Container {Name:weave Image:weaveworks/weave-kube:1.9.4 Command:[/home/weave/launch.sh] Args:[] WorkingDir: Ports:[] EnvFrom:[] Env: 
  Apr 24 10:16:53 master kubelet[13128]: I0424 10:16:53.188091   13128 kuberuntime_manager.go:742] checking backoff for container "weave" in pod "weave-net-5qgvz_kube-system(4b7bb2f0-2691-11e7-bfb6-080027229776)" 
  Apr 24 10:16:53 master kubelet[13128]: I0424 10:16:53.188717   13128 kuberuntime_manager.go:752] Back-off 5m0s restarting failed container=weave pod=weave-net-5qgvz_kube-system(4b7bb2f0-2691-11e7-bfb6-080027229776) 
  Apr 24 10:16:53 master kubelet[13128]: E0424 10:16:53.189136   13128 pod_workers.go:182] Error syncing pod 4b7bb2f0-2691-11e7-bfb6-080027229776 ("weave-net-5qgvz_kube-system(4b7bb2f0-2691-11e7-bfb6-080027229776)"), skipping: fail 
  </code></pre>
  
  <p>Here is systemd log file with restarted kubelet: <a href="https://drive.google.com/open?id=0B3EINM-iyF06SXNvUWRoQWZzS2M" rel="noreferrer">Google Drive</a>.</p>
  
  <p>... I'm not sure what I missed in doc or what happend with kubelet. Can I ask you for help? :] </p>
  
  <p>•        Ubuntu version </p>
  
  <pre><code>cat /etc/os-release 
  NAME="Ubuntu" 
  VERSION="16.04.2 LTS (Xenial Xerus)" 
  ID=ubuntu 
  ID_LIKE=debian 
  PRETTY_NAME="Ubuntu 16.04.2 LTS" 
  VERSION_ID="16.04" 
  HOME_URL="http://www.ubuntu.com/" 
  SUPPORT_URL="http://help.ubuntu.com/" 
  BUG_REPORT_URL="http://bugs.launchpad.net/ubuntu/" 
  VERSION_CODENAME=xenial 
  UBUNTU_CODENAME=xenial 
  </code></pre>
  
  <p>•        Kernel </p>
  
  <pre><code># uname -a 
  Linux ubuntu 4.4.0-72-generic #93-Ubuntu SMP Fri Mar 31 14:07:41 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux 
  </code></pre>
  
  <p>•        Kubectl version </p>
  
  <pre><code># kubectl version 
  Client Version: version.Info{Major:"1", Minor:"6", GitVersion:"v1.6.1", GitCommit:"b0b7a323cc5a4a2019b2e9520c21c7830b7f708e", GitTreeState:"clean", BuildDate:"2017-04-03T20:44:38Z", GoVersion:"go1.7.5", Compiler:"gc", Platform:"linux/amd64"} 
  Server Version: version.Info{Major:"1", Minor:"6", GitVersion:"v1.6.0", GitCommit:"fff5156092b56e6bd60fff75aad4dc9de6b6ef37", GitTreeState:"clean", BuildDate:"2017-03-28T16:24:30Z", GoVersion:"go1.7.5", Compiler:"gc", Platform:"linux/amd64"} 
  </code></pre>
  
  <p>•        Kubeadm version </p>
  
  <pre><code># kubeadm version 
  kubeadm version: version.Info{Major:"1", Minor:"6", GitVersion:"v1.6.1", GitCommit:"b0b7a323cc5a4a2019b2e9520c21c7830b7f708e", GitTreeState:"clean", BuildDate:"2017-04-03T20:33:27Z", GoVersion:"go1.7.5", Compiler:"gc", Platform:"linux/amd64"} 
  </code></pre>
  
  <p>•        Kubelet version </p>
  
  <pre><code># kubelet --version 
  Kubernetes v1.6.1 
  </code></pre>
  
  <p>•        Docker version </p>
  
  <pre><code># docker version 
  Client: 
  Version:      1.11.2 
  API version:  1.23 
  Go version:   go1.5.4 
  Git commit:   b9f10c9 
  Built:        Wed Jun  1 22:00:43 2016 
  OS/Arch:      linux/amd64 
  
  Server: 
  Version:      1.11.2 
  API version:  1.23 
  Go version:   go1.5.4 
  Git commit:   b9f10c9 
  Built:        Wed Jun  1 22:00:43 2016 
  OS/Arch:      linux/amd64 
  </code></pre>