OpenSSH Clearing RSA fingerprints ?


I'm connecting from my windows box to a remove ubuntu box using putty - SSH session.  When I first connect i get the putty alert about accepting the new server host key and also shows the RSA fingerprint.  I've accept the key so everytime I make a ssh server it works without the prompt and I can login to the linux box

What I want to know is how do I delete this key on the server so when I use my pc to connect  remotely the prompt comes up again.  I've tried to delete the fingerprint id from known_hosts and restart the SSH server but I connected straight away Essentially I want to clear all entries on the server so my PC would be given a new key

The odd thing is even after I've delete all the entries from the Know_hosts file I can still connect via ssh to the server ?   Shouldn't it record a new fingerprint ?

Hope this makes sense Your input would be most appreciated
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upanwarConnect With a Mentor Commented:
With which user you login to your Linux box, It is root or any other.

Login to your Linux Box and execute below given command.

# vi ~/.ssh/known_hosts  

Now search the hostname or IP of your Windows box in that file and remove that line with dd then save and exit that file.

Here ~ refers to home directory of current user so no matter from which user you have logged in. It will modify that user's known_host file.

There is one more way to achieve your goal.

ssh-keygen -R <Hostname or IP address of your Linux Box>

It will give you message that
known_hosts updated
Original contents retained as known_hosts.old

Hm perhaps I don't understand correctly

If you connect from a windows putty client to a server, then you have to clean up on the windows putty client side

putty stores the fingerprints in the windows registry:

look at

See also:

CobraitiAuthor Commented:
Thanks. That worked :)
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