<p>I am trying to setup a basic k8s cluster </p>

<p>After doing a kubeadm init --pod-network-cidr=10.244.0.0/16, the coredns pods are stuck in ContainerCreating   status</p>

<pre><code>NAME                            READY   STATUS              RESTARTS   AGE
coredns-6955765f44-2cnhj        0/1     ContainerCreating   0          43h
coredns-6955765f44-dnphb        0/1     ContainerCreating   0          43h
etcd-perf1                      1/1     Running             0          43h
kube-apiserver-perf1            1/1     Running             0          43h
kube-controller-manager-perf1   1/1     Running             0          43h
kube-flannel-ds-amd64-smpbk     1/1     Running             0          43h
kube-proxy-6zgvn                1/1     Running             0          43h
kube-scheduler-perf1            1/1     Running             0          43h

</code></pre>

<p>OS-IMAGE: Ubuntu 16.04.6 LTS
KERNEL-VERSION: 4.4.0-142-generic
CONTAINER-RUNTIME: docker://19.3.5</p>

<p>Errors from journalctl -xeu kubelet command</p>

<pre><code>Jan 02 10:31:44 perf1 kubelet[11901]: 2020-01-02 10:31:44.112 [INFO][10207] k8s.go 228: Using Calico IPAM
Jan 02 10:31:44 perf1 kubelet[11901]: E0102 10:31:44.118281   11901 cni.go:385] Error deleting kube-system_coredns-6955765f44-2cnhj/12cd9435dc905c026bbdb4a1954fc36c82ede1d703b040a3052ab3370445abbf from
Jan 02 10:31:44 perf1 kubelet[11901]: E0102 10:31:44.118828   11901 remote_runtime.go:128] StopPodSandbox "12cd9435dc905c026bbdb4a1954fc36c82ede1d703b040a3052ab3370445abbf" from runtime service failed:
Jan 02 10:31:44 perf1 kubelet[11901]: E0102 10:31:44.118872   11901 kuberuntime_manager.go:898] Failed to stop sandbox {"docker" "12cd9435dc905c026bbdb4a1954fc36c82ede1d703b040a3052ab3370445abbf"}
Jan 02 10:31:44 perf1 kubelet[11901]: E0102 10:31:44.118917   11901 kuberuntime_manager.go:676] killPodWithSyncResult failed: failed to "KillPodSandbox" for "e44bc42f-0b8d-40ad-82a9-334a1b1c8e40" with
Jan 02 10:31:44 perf1 kubelet[11901]: E0102 10:31:44.118939   11901 pod_workers.go:191] Error syncing pod e44bc42f-0b8d-40ad-82a9-334a1b1c8e40 ("coredns-6955765f44-2cnhj_kube-system(e44bc42f-0b8d-40ad-
Jan 02 10:31:47 perf1 kubelet[11901]: W0102 10:31:47.081709   11901 cni.go:331] CNI failed to retrieve network namespace path: cannot find network namespace for the terminated container "747c3cc9455a7d
Jan 02 10:31:47 perf1 kubelet[11901]: 2020-01-02 10:31:47.113 [INFO][10267] k8s.go 228: Using Calico IPAM
Jan 02 10:31:47 perf1 kubelet[11901]: E0102 10:31:47.118526   11901 cni.go:385] Error deleting kube-system_coredns-6955765f44-dnphb/747c3cc9455a7db202ab14576d15509d8ef6967c6349e9acbeff2207914d3d53 from
Jan 02 10:31:47 perf1 kubelet[11901]: E0102 10:31:47.119017   11901 remote_runtime.go:128] StopPodSandbox "747c3cc9455a7db202ab14576d15509d8ef6967c6349e9acbeff2207914d3d53" from runtime service failed:
Jan 02 10:31:47 perf1 kubelet[11901]: E0102 10:31:47.119052   11901 kuberuntime_manager.go:898] Failed to stop sandbox {"docker" "747c3cc9455a7db202ab14576d15509d8ef6967c6349e9acbeff2207914d3d53"}
Jan 02 10:31:47 perf1 kubelet[11901]: E0102 10:31:47.119098   11901 kuberuntime_manager.go:676] killPodWithSyncResult failed: failed to "KillPodSandbox" for "52ffb25e-06c7-4cc6-be70-540049a6be20" with
Jan 02 10:31:47 perf1 kubelet[11901]: E0102 10:31:47.119119   11901 pod_workers.go:191] Error syncing pod 52ffb25e-06c7-4cc6-be70-540049a6be20 ("coredns-6955765f44-dnphb_kube-system(52ffb25e-06c7-4cc6-
</code></pre>

<p>I have tried kubdeadm reset as well but no luck so far</p>

Harish Gupta
<p>Looks like the issue was because I tried switching from calico to flannel cni. Following the steps mentioned here has resolved the issue for me</p>

<p><a href="https://stackoverflow.com/questions/53900779/pods-failed-to-start-after-switch-cni-plugin-from-flannel-to-calico-and-then-fla">Pods failed to start after switch cni plugin from flannel to calico and then flannel</a></p>

<p>Additionally you may have to clear the contents of <code>/etc/cni/net.d</code></p>
