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Jared Nielsen
Jared Nielsen

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How to fix the git warning "ECDSA host key for 'github.com' differs from the key for the IP address '140.82.113.3'"

#git #github #troubleshooting #ssh

If GitHub's recent RSA SSH host key update causes your system to throw this error:

Warning: the ECDSA host key for 'github.com' differs from the key for the IP address '140.82.113.3'
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The solution is a quick fix. The next lines of the error will read something like this:

Offending key for IP in ~/.ssh/known_hosts:X
Matching host key in ~/.ssh/known_hosts:Y
Are you sure you want to continue connecting (yes/no)?
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Where X is the line number containing the IP address we want to remove. So...

Run the following command:

vi ~/.ssh/known_hosts
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And ⬇️ to line X and run the following to delete the line and exit vi:

dd
:x
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Voila!

Top comments (3)

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drmercer profile image
Dan Mercer •

You can also do sed -e "Xd" ~/.ssh/known_hosts to delete line X (the line number from above). A little bit easier than using Vim. 😅

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xtofl profile image
xtofl •

Would you need the in-place argument? sed -i "Xd" ~/.ssh/known_hosts?

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xtofl profile image
xtofl •

While this does the trick, it bypasses the tools that are offered by the ssh package.

The ssh package has a tool called ssh-keygen with a 'remove' subcommand -R.

So you should be using ssh-keygen -R 140.82.113.3.


Warning: the ECDSA host key for 'github.com' differs from
the key for the IP address '140.82.121.3'
Offending key for IP in /home/xtofl/.ssh/known_hosts:12
Matching host key in /home/xtofl/ssh/known_hosts:58
Are you sure you want to continue connecting (yes/no)?
^C


09:28 $ ssh-keygen -R 140.82.121.3
# Host 140.82.121.3 found: line 12
/home/xtofl/.ssh/known_hosts updated.
Original contents retained as /home/xtofl/.ssh/known_hosts.old
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