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What is ECDSA host key?
A host key is a cryptographic key used for authenticating computers in the SSH protocol. Host keys are key pairs, typically using the RSA, DSA, or ECDSA algorithms. Public host keys are stored on and/or distributed to SSH clients, and private keys are stored on SSH servers.
Where is my ECDSA host key?
One pretty easy way is to use ssh-keyscan. This command will request keys from the remote server. For example if I wanted the rsa, ecdsa, and ed25519 host keys from demo.example.org I might use this command.
How to fix warning about ECDSA host key when SSH connection?
Add correct host key in /Users/dalanz/.ssh/known_hosts to get rid of this message. Offending ECDSA key in /Users/dalanz/.ssh/known_hosts:9 ECDSA host key for 192.168.56.101 has changed and you have requested strict checking.
What’s the fingerprint for the ECDSA host key?
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:p4ZGs+YjsBAw26tn2a+HPkga1dPWWAWX+NEm4Cv4I9s. Please contact your system administrator.
Where can I find the offending ECDSA key?
Offending ECDSA key in /Users/dalanz/.ssh/known_hosts:9 ECDSA host key for 192.168.56.101 has changed and you have requested strict checking. Host key verification failed. Remove the cached key for the IP address on the local machine: $ ssh-keygen -R 192.168.56.101 # Host 192.168.56.101 found: line 9 /Users/dalanz/.ssh/known_hosts updated.
What does warning remote host identification has changed mean?
This is called a man-in-the-middle attack. This scenario is exactly what the “WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!” message is trying to warn you about. Of course, this isn’t always the case, and there are many reasons for the ECDSA key fingerprint to change for a server.