WARNING: REMOTE HOST IDENTIFICATION HAD CHANGED!

  less than a minute  

If you ssh to your controller it failed with the warning:

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@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
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IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that a host key has just been changed.
The fingerprint for the ECDSA key sent by the remote host is
SHA256:uT5DMddzCBPau3a0q6gfUpILyDTOFB/3rT19GjeaINQ.
Please contact your system administrator.
Add correct host key in /home/philippe/.ssh/known_hosts to get rid of this message.
Offending ECDSA key in /home/philippe/.ssh/known_hosts:4
  remove with:
  ssh-keygen -f "/home/philippe/.ssh/known_hosts" -R "192.168.2.100"
ECDSA host key for 192.168.2.100 has changed and you have requested strict checking.

Check out SSH troubleshooting to resolve this issue.