[root@node03 ~]# kubeadm join 192.168.99.10:6443 --token ysrv0l.1d9f6g1ecgv5yryl \
>         --discovery-token-ca-cert-hash sha256:9f1adb5597a3df3df6afc86c8610792fd2e89840657380ddc56d9f4ba81d4c97 --ignore-preflight-errors=Swap
[preflight] Running pre-flight checks
	[WARNING Swap]: swap is enabled; production deployments should disable swap unless testing the NodeSwap feature gate of the kubelet
error execution phase preflight: couldn't validate the identity of the API Server: could not find a JWS signature in the cluster-info ConfigMap for token ID "ysrv0l"
To see the stack trace of this error execute with --v=5 or higher

As mentioned above, I read the last line of the error message mainly because the original token has expired

You can verify with the following command that there is no output

$ kubeadm token list
# There is no output here, indicating that there are no surviving tokens

Solution: Generate a new token

# execute in the note of master
kubeadm token create --print-join-command --ttl=0

Where --ttl=0 means that the generated token will never expire If there is no --ttl parameter, the default effective time is 24 hours