Kubeadm: Kubeadm HA cluster join - couldn't validate the identity of the API Server

[vishwakhrushi]

BUG REPORT

Versions

kubeadm version (use kubeadm version):
kubeadm version: &version.Info{Major:"1", Minor:"13", GitVersion:"v1.13.4", GitCommit:"c27b913fddd1a6c480c229191a087698aa92f0b1", GitTreeState:"clean", BuildDate:"2019-02-28T13:35:32Z", GoVersion:"go1.11.5", Compiler:"gc", Platform:"linux/amd64"}
Environment:

• Kubernetes version (use kubectl version): v1.13.4
• Cloud provider or hardware configuration: bare-metal
• OS (e.g. from /etc/os-release): CentOS 7.6
• Kernel (e.g. uname -a): Linux 3.10.0-957.5.1.el7.x86_64 #1 SMP Fri Feb 1 14:54:57 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
• Others:

What happened?

Trying to setup a HA cluster with stacked control plane and etcds. Initiated the cluster using kubeadm on the first master node and copied all the necessary certs and files to the remaining two master nodes. When running the join command to join them to the cluster its giving out the following error.
sh ~]$ sudo kubeadm join <load_balancer_dns_name>:6443 --token xxxxx.xxxxxxxxxx --discovery-token-ca-cert-hash sha256:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx --experimental-control-plane [preflight] Running pre-flight checks couldn't validate the identity of the API Server: encoding/hex: invalid byte: U+006E 'n'

What you expected to happen?

The node should join the cluster as secondary master to the cluster

Anything else we need to know?

Running an F5-loadbalancer with healthcheck on 6443 ports pointing to the three master nodes.

[neolit123]

could this be a case where your tokens include the offending n character?
are these tokens generated by kubeadm or did you create them?

you can also run kubeadm join with e.g -v=6 to show more details of where this happens.
sharing this output on pastebin.com or gist would be ideal.

thanks.

[timothysc]

Closing due to inactivity.