unable to initiate kubeadm in the controller node , It says port in use

Question

sudo kubeadm init I0609 02:20:26.963781 3600 version.go:252] remote version is much newer: v1.21.1; falling back to: stable-1.18 W0609 02:20:27.069495 3600 configset.go:202]

WARNING: kubeadm cannot validate component configs `for API groups [kubelet.config.k8s.io kubeproxy.config.k8s.io]`
`[init] Using Kubernetes version: v1.18.19`
`[preflight] Running pre-flight checks`
`error execution phase preflight: [preflight] Some fatal errors occurred:`
`[ERROR Port-10259]: Port 10259 is in use`
`[ERROR Port-10257]: Port 10257 is in use`
`[ERROR FileAvailable--etc-kubernetes-manifests-kube-apiserver.yaml]: `/etc/kubernetes/manifests/kube-apiserver.yaml already exists`
`[ERROR FileAvailable--etc-kubernetes-manifests-kube-controller-manager.yaml]:` `/etc/kubernetes/manifests/kube-controller-manager.yaml already exists`
`[ERROR FileAvailable--etc-kubernetes-manifests-kube-scheduler.yaml]:` /etc/kubernetes/manifests/kube-scheduler.yaml already exists
`[ERROR FileAvailable--etc-kubernetes-manifests-etcd.yaml]: /etc/kubernetes/manifests/etcd.yaml already exists`
`[ERROR Port-10250]: Port 10250 is in use`
`[ERROR Port-2379]: Port 2379 is in use`
`[ERROR Port-2380]: Port 2380 is in use`
`[ERROR DirAvailable--var-lib-etcd]: /var/lib/etcd is not empty`
 [preflight] If you know what you are doing, you can make a check non-fatal with `--ignore-preflight-errors=...`
 To see the stack trace of this error execute with --v=5 or higher

Answer 1

Hi and welcome to Stack Overflow.

"Port in use" means that there's a process running that uses that port. So you need to stop that process. Since you already ran kubeadm init once, it must have already changed a number of things.

First run kubeadm reset to undo all of the changes from the first time you ran it.

Then run systemctl restart kubelet.

Finally, when you run kubeadm init you should no longer get the error.

Even after following the above steps , if you get this error:

[ERROR DirAvailable--var-lib-etcd]: /var/lib/etcd is not empty
[preflight] If you know what you are doing, you can make a check non-fatal with `--ignore-preflight-errors=...`

Then, remove the etcd folder (/var/lib/etcd) before you run kubeadm init.

Note:

1. This solution worked for other users.

2. The warning itself is not an issue, it's just warning that kubeadm no longer validates the KubeletConfiguration, KubeProxyConfiguration that it feeds to the kubelet, kube-proxy components.