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Error running docker swarm join: "remote ca does not match fingerprint"?

The command (docker swarm join) and all related docs seem simple to just learn and try.
But its error sometimes is too vague and hard to resolve, especially there is few thing we can find via searching.

As for this error, the Google search result shows just 3 pages and many entries are duplicated.

I’m really stuck at this and hope someone here could give me some suggestion to try.

My environment:

– I have 2 machines, one runs Windows 10 Enterprise and the other runs Ubuntu. Both are connected OK via LAN. The IP of Windows machine is gateway to which the Linux machine connects. All required ports (as documented) are open on both machines, including 2377 - TCP, 7946 - TCP & UDP and 4789 - UDP.

In the Windows machine, I’ve already run the following command successfully:

docker swarm init --advertise-addr

here the IP is the IP of the default virtual switch (the Linux machine is run in a VM created by Hyper-v).

In the Linux machine, I’ve tried the following command (which raised the error):

sudo docker swarm join --token ...

I copied the exact token (replacing the … in the above command) from the output of the command docker swarm init run in the Windows machine.

After that it reports the error as in the title.
I’m sure that some docker learners have surely experienced this error. It may be hard to tell exactly what’s wrong but I hope someone here could give me some suggestions to help diagnose and attempt to solve it.