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SSH Hostkey Issue

Why do it get this error message / warning when I try to establish a connection via SSH?

What is it? How can I get rid of it? 

    @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
    @ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
    @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
    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 ED25519 key sent by the remote host is
    SHA256:
    Please contact your system administrator.
    Add correct host key in /home/user/.ssh/known_hosts to get rid of this message.
    Offending ED25519 key in /home/user/.ssh/known_hosts:67
    Host key for IP has changed and you have requested strict checking.
    Host key verification failed.

This happens when the key of the system you want to connect to, is not the same as the one your computer has stored along with the IP-Address. Or in short:

Same IP-Address, different device.

Please only ignore this warning if you are 100% sure, that the device you want to connect to is the right one.

We can use following command to replace the the old key with the new one: 


    $ ssh-keygen -R IP-ADDRESS

After that, you should be able to connect to the device without problems.



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