kubeadm: kubeadm init/join CRI preflight check fails unnecessarily

What keywords did you search in kubeadm issues before filing this one?

I searched for: unable to check if the container runtime at “/var/run/dockershim.sock” is running

I found #657 but it was already closed.

Is this a BUG REPORT or FEATURE REQUEST?

BUG REPORT

Versions

kubeadm version (use kubeadm version):

root@mjs-worker-dal10-a:~# kubeadm version
kubeadm version: &version.Info{Major:"1", Minor:"10", GitVersion:"v1.10.2", GitCommit:"81753b10df112992bf51bbc2c2f85208aad78335", GitTreeState:"clean", BuildDate:"2018-04-27T09:10:24Z", GoVersion:"go1.9.3", Compiler:"gc", Platform:"linux/amd64"}

Environment:

• Kubernetes version (use kubectl version):

root@mjs-worker-dal10-a:~# kubectl version
Client Version: version.Info{Major:"1", Minor:"10", GitVersion:"v1.10.2", GitCommit:"81753b10df112992bf51bbc2c2f85208aad78335", GitTreeState:"clean", BuildDate:"2018-04-27T09:22:21Z", GoVersion:"go1.9.3", Compiler:"gc", Platform:"linux/amd64"}
The connection to the server localhost:8080 was refused - did you specify the right host or port?

• Cloud provider or hardware configuration: No kube CloudProvider. SoftLayer VM with 16 CPUs and 32 GB of main memory.

• OS (e.g. from /etc/os-release): 16.04.4 LTS

• Kernel (e.g. uname -a): Linux mjs-worker-dal10-a 4.4.0-112-generic #135-Ubuntu SMP Fri Jan 19 11:48:36 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

• Others:

What happened?

root@mjs-worker-dal10-a:~# kubeadm join --token t3c20c.s0s7q3md5lkgn5d6 --discovery-token-ca-cert-hash 1044b1e3ef183d51c50030533d8f33764a2928f8b76193a020eab2d855619ab4 10.171.126.235:6443
[preflight] Running pre-flight checks.
[preflight] Some fatal errors occurred:
	[ERROR CRI]: unable to check if the container runtime at "/var/run/dockershim.sock" is running: fork/exec /usr/local/bin/crictl -r /var/run/dockershim.sock info: no such file or directory
[preflight] If you know what you are doing, you can make a check non-fatal with `--ignore-preflight-errors=...`

I have crictl installed and there is no dockershim running yet.

root@mjs-worker-dal10-a:~# ls -ld /var/run/dock*
drwx------ 6 root root   120 May  8 00:03 /var/run/docker
-rw-r--r-- 1 root root     5 May 12 15:41 /var/run/docker.pid
srw-rw---- 1 root docker   0 May 12 15:41 /var/run/docker.sock

What you expected to happen?

I expected kubeadm to not complain about the fact that it has not made a dockershim yet. I expected #657 to be fixed, since I am using version 1.10.2 of kubeadm.

How to reproduce it (as minimally and precisely as possible)?

Just like #657

Anything else we need to know?