<p>I created a  kubernetes cluster 1 master and 2 worker nodes 2 months ago, 
today one worker node started to fail and I don't know why. I think nothing unusual happened to my worker.</p>

<p>I used flannel and kubeadm to create the cluster and it was working very well.</p>

<p>If I describe the node:</p>

<pre><code>tommy@bxybackend:~$ kubectl describe node bxybackend-node01
Name:               bxybackend-node01
Roles:              &lt;none&gt;
Labels:             beta.kubernetes.io/arch=amd64
                    beta.kubernetes.io/os=linux
                    kubernetes.io/arch=amd64
                    kubernetes.io/hostname=bxybackend-node01
                    kubernetes.io/os=linux
Annotations:        flannel.alpha.coreos.com/backend-data: {"VtepMAC":"06:ca:97:82:50:10"}
                    flannel.alpha.coreos.com/backend-type: vxlan
                    flannel.alpha.coreos.com/kube-subnet-manager: true
                    flannel.alpha.coreos.com/public-ip: 10.168.10.4
                    kubeadm.alpha.kubernetes.io/cri-socket: /var/run/dockershim.sock
                    node.alpha.kubernetes.io/ttl: 0
                    volumes.kubernetes.io/controller-managed-attach-detach: true
CreationTimestamp:  Sun, 03 Nov 2019 09:41:48 -0600
Taints:             node.kubernetes.io/not-ready:NoExecute
                    node.kubernetes.io/not-ready:NoSchedule
Unschedulable:      false
Conditions:
  Type             Status  LastHeartbeatTime                 LastTransitionTime                Reason                       Message
  ----             ------  -----------------                 ------------------                ------                       -------
  MemoryPressure   False   Wed, 11 Dec 2019 11:17:05 -0600   Wed, 11 Dec 2019 10:37:19 -0600   KubeletHasSufficientMemory   kubelet has sufficient memory available
  DiskPressure     False   Wed, 11 Dec 2019 11:17:05 -0600   Wed, 11 Dec 2019 10:37:19 -0600   KubeletHasNoDiskPressure     kubelet has no disk pressure
  PIDPressure      False   Wed, 11 Dec 2019 11:17:05 -0600   Wed, 11 Dec 2019 10:37:19 -0600   KubeletHasSufficientPID      kubelet has sufficient PID available
  Ready            False   Wed, 11 Dec 2019 11:17:05 -0600   Wed, 11 Dec 2019 10:37:19 -0600   KubeletNotReady              Failed to initialize CSINodeInfo: error updating CSINode annotation: timed out waiting for the condition; caused by: the server could not find the requested resource
Addresses:
  InternalIP:  10.168.10.4
  Hostname:    bxybackend-node01
Capacity:
 cpu:                12
 ephemeral-storage:  102684600Ki
 hugepages-1Gi:      0
 hugepages-2Mi:      0
 memory:             14359964Ki
 pods:               110
Allocatable:
 cpu:                12
 ephemeral-storage:  94634127204
 hugepages-1Gi:      0
 hugepages-2Mi:      0
 memory:             14257564Ki
 pods:               110
System Info:
 Machine ID:                 3afa24bb05994ceaaf00e7f22b9322ab
 System UUID:                80951742-F69F-6487-F2F7-BE2FB7FEFBF8
 Boot ID:                    115fbacc-143d-4007-90e4-7fdcb5462680
 Kernel Version:             4.15.0-72-generic
 OS Image:                   Ubuntu 18.04.3 LTS
 Operating System:           linux
 Architecture:               amd64
 Container Runtime Version:  docker://18.9.7
 Kubelet Version:            v1.17.0
 Kube-Proxy Version:         v1.17.0
PodCIDR:                     10.244.1.0/24
PodCIDRs:                    10.244.1.0/24
Non-terminated Pods:         (2 in total)
  Namespace                  Name                           CPU Requests  CPU Limits  Memory Requests  Memory Limits  AGE
  ---------                  ----                           ------------  ----------  ---------------  -------------  ---
  kube-system                kube-flannel-ds-amd64-sslbg    100m (0%)     100m (0%)   50Mi (0%)        50Mi (0%)      8m31s
  kube-system                kube-proxy-c5gxc               0 (0%)        0 (0%)      0 (0%)           0 (0%)         8m52s
Allocated resources:
  (Total limits may be over 100 percent, i.e., overcommitted.)
  Resource           Requests   Limits
  --------           --------   ------
  cpu                100m (0%)  100m (0%)
  memory             50Mi (0%)  50Mi (0%)
  ephemeral-storage  0 (0%)     0 (0%)
Events:
  Type     Reason                   Age                  From                           Message
  ----     ------                   ----                 ----                           -------
  Warning  SystemOOM                52m                  kubelet, bxybackend-node01     System OOM encountered, victim process: dotnet, pid: 12170
  Normal   NodeHasNoDiskPressure    52m (x12 over 38d)   kubelet, bxybackend-node01     Node bxybackend-node01 status is now: NodeHasNoDiskPressure
  Normal   NodeHasSufficientPID     52m (x12 over 38d)   kubelet, bxybackend-node01     Node bxybackend-node01 status is now: NodeHasSufficientPID
  Normal   NodeNotReady             52m (x6 over 23d)    kubelet, bxybackend-node01     Node bxybackend-node01 status is now: NodeNotReady
  Normal   NodeHasSufficientMemory  52m (x12 over 38d)   kubelet, bxybackend-node01     Node bxybackend-node01 status is now: NodeHasSufficientMemory
  Warning  ContainerGCFailed        52m (x3 over 6d23h)  kubelet, bxybackend-node01     rpc error: code = DeadlineExceeded desc = context deadline exceeded
  Normal   NodeReady                52m (x13 over 38d)   kubelet, bxybackend-node01     Node bxybackend-node01 status is now: NodeReady
  Normal   NodeAllocatableEnforced  43m                  kubelet, bxybackend-node01     Updated Node Allocatable limit across pods
  Warning  SystemOOM                43m                  kubelet, bxybackend-node01     System OOM encountered, victim process: dotnet, pid: 9699
  Warning  SystemOOM                43m                  kubelet, bxybackend-node01     System OOM encountered, victim process: dotnet, pid: 12639
  Warning  SystemOOM                43m                  kubelet, bxybackend-node01     System OOM encountered, victim process: dotnet, pid: 16194
  Warning  SystemOOM                43m                  kubelet, bxybackend-node01     System OOM encountered, victim process: dotnet, pid: 19618
  Warning  SystemOOM                43m                  kubelet, bxybackend-node01     System OOM encountered, victim process: dotnet, pid: 12170
  Normal   Starting                 43m                  kubelet, bxybackend-node01     Starting kubelet.
  Normal   NodeHasSufficientMemory  43m (x2 over 43m)    kubelet, bxybackend-node01     Node bxybackend-node01 status is now: NodeHasSufficientMemory
  Normal   NodeHasSufficientPID     43m (x2 over 43m)    kubelet, bxybackend-node01     Node bxybackend-node01 status is now: NodeHasSufficientPID
  Normal   NodeNotReady             43m                  kubelet, bxybackend-node01     Node bxybackend-node01 status is now: NodeNotReady
  Normal   NodeHasNoDiskPressure    43m (x2 over 43m)    kubelet, bxybackend-node01     Node bxybackend-node01 status is now: NodeHasNoDiskPressure
  Normal   Starting                 42m                  kubelet, bxybackend-node01     Starting kubelet.
</code></pre>

<p>If I watch syslog in the worker: </p>

<pre><code>Dec 11 11:20:10 bxybackend-node01 kubelet[19331]: I1211 11:20:10.552152   19331 kuberuntime_manager.go:981] updating runtime config through cri with podcidr 10.244.1.0/24
Dec 11 11:20:10 bxybackend-node01 kubelet[19331]: I1211 11:20:10.552162   19331 kubelet_node_status.go:294] Setting node annotation to enable volume controller attach/detach
Dec 11 11:20:10 bxybackend-node01 kubelet[19331]: I1211 11:20:10.552352   19331 docker_service.go:355] docker cri received runtime config &amp;RuntimeConfig{NetworkConfig:&amp;NetworkConfig{PodCidr:10.244.1.0/24,},}
Dec 11 11:20:10 bxybackend-node01 kubelet[19331]: I1211 11:20:10.552600   19331 kubelet_network.go:77] Setting Pod CIDR:  -&gt; 10.244.1.0/24
Dec 11 11:20:10 bxybackend-node01 kubelet[19331]: I1211 11:20:10.555142   19331 kubelet_node_status.go:70] Attempting to register node bxybackend-node01
Dec 11 11:20:10 bxybackend-node01 kubelet[19331]: I1211 11:20:10.652843   19331 reconciler.go:209] operationExecutor.VerifyControllerAttachedVolume started for volume "kube-proxy" (UniqueName: "kubernetes.io/configmap/d6b534db-c32c-491b-a665-cf1ccd6cd089-kube-proxy") pod "kube-proxy-c5gxc" (UID: "d6b534db-c32c-491b-a665-cf1ccd6cd089")
Dec 11 11:20:10 bxybackend-node01 kubelet[19331]: I1211 11:20:10.753179   19331 reconciler.go:209] operationExecutor.VerifyControllerAttachedVolume started for volume "xtables-lock" (UniqueName: "kubernetes.io/host-path/d6b534db-c32c-491b-a665-cf1ccd6cd089-xtables-lock") pod "kube-proxy-c5gxc" (UID: "d6b534db-c32c-491b-a665-cf1ccd6cd089")
Dec 11 11:20:10 bxybackend-node01 kubelet[19331]: I1211 11:20:10.753249   19331 reconciler.go:209] operationExecutor.VerifyControllerAttachedVolume started for volume "lib-modules" (UniqueName: "kubernetes.io/host-path/d6b534db-c32c-491b-a665-cf1ccd6cd089-lib-modules") pod "kube-proxy-c5gxc" (UID: "d6b534db-c32c-491b-a665-cf1ccd6cd089")
Dec 11 11:20:10 bxybackend-node01 kubelet[19331]: I1211 11:20:10.753285   19331 reconciler.go:209] operationExecutor.VerifyControllerAttachedVolume started for volume "kube-proxy-token-ztrh4" (UniqueName: "kubernetes.io/secret/d6b534db-c32c-491b-a665-cf1ccd6cd089-kube-proxy-token-ztrh4") pod "kube-proxy-c5gxc" (UID: "d6b534db-c32c-491b-a665-cf1ccd6cd089")
Dec 11 11:20:10 bxybackend-node01 kubelet[19331]: I1211 11:20:10.753316   19331 reconciler.go:209] operationExecutor.VerifyControllerAttachedVolume started for volume "run" (UniqueName: "kubernetes.io/host-path/6a2299cf-63a4-4e96-8b3b-acd373de12c2-run") pod "kube-flannel-ds-amd64-sslbg" (UID: "6a2299cf-63a4-4e96-8b3b-acd373de12c2")
Dec 11 11:20:10 bxybackend-node01 kubelet[19331]: I1211 11:20:10.753342   19331 reconciler.go:209] operationExecutor.VerifyControllerAttachedVolume started for volume "cni" (UniqueName: "kubernetes.io/host-path/6a2299cf-63a4-4e96-8b3b-acd373de12c2-cni") pod "kube-flannel-ds-amd64-sslbg" (UID: "6a2299cf-63a4-4e96-8b3b-acd373de12c2")
Dec 11 11:20:10 bxybackend-node01 kubelet[19331]: I1211 11:20:10.753461   19331 reconciler.go:209] operationExecutor.VerifyControllerAttachedVolume started for volume "flannel-cfg" (UniqueName: "kubernetes.io/configmap/6a2299cf-63a4-4e96-8b3b-acd373de12c2-flannel-cfg") pod "kube-flannel-ds-amd64-sslbg" (UID: "6a2299cf-63a4-4e96-8b3b-acd373de12c2")
Dec 11 11:20:10 bxybackend-node01 kubelet[19331]: I1211 11:20:10.753516   19331 reconciler.go:209] operationExecutor.VerifyControllerAttachedVolume started for volume "flannel-token-ts2qt" (UniqueName: "kubernetes.io/secret/6a2299cf-63a4-4e96-8b3b-acd373de12c2-flannel-token-ts2qt") pod "kube-flannel-ds-amd64-sslbg" (UID: "6a2299cf-63a4-4e96-8b3b-acd373de12c2")
Dec 11 11:20:10 bxybackend-node01 kubelet[19331]: I1211 11:20:10.753531   19331 reconciler.go:156] Reconciler: start to sync state
Dec 11 11:20:12 bxybackend-node01 kubelet[19331]: I1211 11:20:12.052813   19331 kubelet_node_status.go:112] Node bxybackend-node01 was previously registered
Dec 11 11:20:12 bxybackend-node01 kubelet[19331]: I1211 11:20:12.052921   19331 kubelet_node_status.go:73] Successfully registered node bxybackend-node01
Dec 11 11:20:13 bxybackend-node01 kubelet[19331]: E1211 11:20:13.051159   19331 csi_plugin.go:267] Failed to initialize CSINodeInfo: error updating CSINode annotation: timed out waiting for the condition; caused by: the server could not find the requested resource
Dec 11 11:20:16 bxybackend-node01 kubelet[19331]: E1211 11:20:16.051264   19331 csi_plugin.go:267] Failed to initialize CSINodeInfo: error updating CSINode annotation: timed out waiting for the condition; caused by: the server could not find the requested resource
Dec 11 11:20:18 bxybackend-node01 kubelet[19331]: E1211 11:20:18.451166   19331 csi_plugin.go:267] Failed to initialize CSINodeInfo: error updating CSINode annotation: timed out waiting for the condition; caused by: the server could not find the requested resource
Dec 11 11:20:21 bxybackend-node01 kubelet[19331]: E1211 11:20:21.251289   19331 csi_plugin.go:267] Failed to initialize CSINodeInfo: error updating CSINode annotation: timed out waiting for the condition; caused by: the server could not find the requested resource
Dec 11 11:20:25 bxybackend-node01 kubelet[19331]: E1211 11:20:25.019276   19331 csi_plugin.go:267] Failed to initialize CSINodeInfo: error updating CSINode annotation: timed out waiting for the condition; caused by: the server could not find the requested resource
Dec 11 11:20:46 bxybackend-node01 kubelet[19331]: E1211 11:20:46.772862   19331 csi_plugin.go:267] Failed to initialize CSINodeInfo: error updating CSINode annotation: timed out waiting for the condition; caused by: the server could not find the requested resource
Dec 11 11:20:46 bxybackend-node01 kubelet[19331]: F1211 11:20:46.772895   19331 csi_plugin.go:281] Failed to initialize CSINodeInfo after retrying
Dec 11 11:20:46 bxybackend-node01 systemd[1]: kubelet.service: Main process exited, code=exited, status=255/n/a
Dec 11 11:20:46 bxybackend-node01 systemd[1]: kubelet.service: Failed with result 'exit-code'.
</code></pre>

<p>During your kubeadm install your are supposed to run the following command to hold  kubelet, kubeadm and kubectl packages and prevent them from getting upgraded mistakenly. </p>

<pre><code>$ sudo apt-mark hold kubelet kubeadm kubectl
</code></pre>

<p>I've reproduced your scenario and what happened to your cluster is that 3 days ago, a new version of Kubernetes was released (v 1.17.0) and your kubelet got got upgraded accidentally. </p>

<p>On the new Kubernetes some changes where made on <a href="https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG-1.17.md#changes" rel="nofollow noreferrer">CSI</a> and that's why you have some problems in this node. </p>

<p>I suggest you to drain this node, setup a new one with Kubernetes 1.16.2 and join the new one to your cluster. </p>

<p>To drain this node you need to run:</p>

<pre><code>$ kubectl drain bxybackend-node01 --delete-local-data --force --ignore-daemonsets
</code></pre>

<p>Optionally you can downgrade your kubelet to previous version using the following command: </p>

<pre><code>$ sudo apt-get install kubelet=1.16.2-00
</code></pre>

<p>Don't forget to mark your kubelet to prevent it from being upgraded again: </p>

<pre><code>$ sudo apt-mark hold kubelet
</code></pre>

<p>You can use the command <code>apt-mark showhold</code> to list all held packages and make sure kubelet, kubeadm and kubectl are on hold. </p>

<p><strong>To upgrade from 1.16.x to 1.17.x follow this <a href="https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/kubeadm-upgrade/" rel="nofollow noreferrer">guide</a> from Kubernetes Documentation. I've validated it and it works as intended.</strong> </p>
