SSH: Agent Admitted Failure To Sign Using The Key Error And Solution

I‘ve recently regenrated and uploaded a new public ssh-key using the ssh-copy-id command. Now I’m getting the following error:

ssh root@server3
Agent admitted failure to sign using the key.
root@server3’s password:

How do I fix this problem?

Tutorial details
Difficulty level	Easy
Root privileges	No
Requirements	ssh-add/Linux
Est. reading time	1m

To fix this problem you need logout of your Unix / Linux / OS X / BSD desktop session and log back in again to force the agent to forget identity. Another recommend option is to run the ssh-add command to add RSA or DSA identities to the authentication agent. This will fix your problem without login out from the current session. The syntax is as follows:

$ ssh-add

Pro tip: If your key located in different path or does not have the default filename, you will need to pass the path to ssh-add command as follows:

$ ssh-add /path/to/my/ssh_key
$ ssh-add ~/.ssh/server3_key

See ssh-add(1) command man page for more information.

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