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.
I used flannel and kubeadm to create the cluster and it was working very well.
If I describe the node:
tommy@bxybackend:~$ kubectl describe node bxybackend-node01
Name: bxybackend-node01
Roles: <none>
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.
If I watch syslog in the worker:
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 &RuntimeConfig{NetworkConfig:&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: -> 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'.
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.
$ sudo apt-mark hold kubelet kubeadm kubectl
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.
On the new Kubernetes some changes where made on CSI and that's why you have some problems in this node.
I suggest you to drain this node, setup a new one with Kubernetes 1.16.2 and join the new one to your cluster.
To drain this node you need to run:
$ kubectl drain bxybackend-node01 --delete-local-data --force --ignore-daemonsets
Optionally you can downgrade your kubelet to previous version using the following command:
$ sudo apt-get install kubelet=1.16.2-00
Don't forget to mark your kubelet to prevent it from being upgraded again:
$ sudo apt-mark hold kubelet
You can use the command apt-mark showhold
to list all held packages and make sure kubelet, kubeadm and kubectl are on hold.
To upgrade from 1.16.x to 1.17.x follow this guide from Kubernetes Documentation. I've validated it and it works as intended.
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