一、报错信息

[preflight] WARNING: JoinControlPane.controlPlane settings will be ignored when control-plane flag is not set.
[preflight] Running pre-flight checks
error execution phase preflight: [preflight] Some fatal errors occurred:
[ERROR FileAvailable--etc-kubernetes-kubelet.conf]: /etc/kubernetes/kubelet.conf already exists
[ERROR FileAvailable--etc-kubernetes-bootstrap-kubelet.conf]: /etc/kubernetes/bootstrap-kubelet.conf already exists
[ERROR FileAvailable--etc-kubernetes-pki-ca.crt]: /etc/kubernetes/pki/ca.crt already exists

二、解决方案

原因是：一些配置文件与服务已经存在

#重置kubeadm 
kubeadm reset

#删除k8s配置文件和证书文件
rm -rf /etc/kubernetes/kubelet.conf /etc/kubernetes/pki/ca.crt #删除k8s配置文件和证书文件

 kubeadm join 192.168.117.100:6443 --token 0l3qfv.mx9js9pfl1ft4avd     --discovery-token-ca-cert-hash sha256:cee17915cc12a2ba319629e41b6460a25725652bad41cc138f2b8d4407821c67

亲测完美解决 SUCCESS