Kubectl connectivity issue

Question

I installed first ectd, kubeapiserver and kubelet using systemd service. The services are running fine and listening to all required ports.

When I run kubectl cluster-info , I get below output

Kubernetes master is running at http://localhost:8080

When I run kubectl get componentstatuses, then I get below output

etcd-0               Healthy     {"health": "true"}

But running kubectl get nodes , I get below error

Error from server (ServerTimeout): the server cannot complete the requested operation at this time, try again later (get nodes)

Can anybody help me out on this.

Answer 1

For the message:

:~# k get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME                 STATUS      MESSAGE                                                                                       ERROR
controller-manager   Unhealthy   Get "http://127.0.0.1:10252/healthz": dial tcp 127.0.0.1:10252: connect: connection refused   
scheduler            Unhealthy   Get "http://127.0.0.1:10251/healthz": dial tcp 127.0.0.1:10251: connect: connection refused   
etcd-0               Healthy     {"health":"true"} 
--------

Modify the following files on all master nodes:

$ sudo vim /etc/kubernetes/manifests/kube-scheduler.yaml

Comment or delete the line:

- --port=0

in (spec->containers->command->kube-scheduler)

$ sudo vim /etc/kubernetes/manifests/kube-controller-manager.yaml

Comment or delete the line:

- --port=0

in (spec->containers->command->kube-controller-manager)

Then restart kubelet service:

$ sudo systemctl restart kubelet.service