For this demonstration, I remove the 192.168.1.84 entry from the known_hosts file and then connect to the new host at that address, so you can see a comparison of what happens in the process. The easy solution to this problem is to remove the known_hosts file and allow new keys to be generated for each host you connect to. Ken,192.168.1.69 ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBB53lh2RyFiMfJFKBkLa643lS4GGILG6oVGq33KyBSgaDU2ZHryYak1FU1HcPa6Xb/xYqEUugv9cOXFRwajbrmg=ġ92.168.1.84 ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBMGjMsJPX4bfdEnVy59Uf2VhH1oAt7Zemd5bfSoSGxX69HBcjkekO/LkEZUlhVplBlHFqJBqs2gWYp3zVDCTwr4=ġ92.168.1.64 ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBIkK9WylcZcgjT7gUz9DMLehUBApION1CLiBVc3Pa/YfAbIDUlIWta12zL5B12RmBXgoYvntdW5rcowPiqjL0/o= ssh/known_hostsġ92.168.1.97 ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBMJWpXf8Ou/XJ1Q5YcIS5Me4GgN1F7AYHbvIPayfGqwd90kvhQygrPCYEqVdw44lEOIZe+DEKP4F6Otdt38yf68=ġ92.168.1.101 ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBJRNTZm8M9IYYN3uJL/圜Pv4EJRMDZkkcnt1CY8L6OR84wstYdhqtNqV0v/LQiz/AoRbHKxPTdjXfIOrc1vYDHc= To view its contents, enter the following command: $ cat. The aforementioned known_hosts file is a simple text file that lives inside a hidden directory (. One that is also known to your system, but with a different fingerprint. Regardless of how it happened, the system you were interested in connecting to has a new IP address. I have my reasons for this strong opinion, which I'll share in another article later.) Only end-user devices should have the dubious privilege of acquiring random IP addresses. The same goes for any support components, such as routers, switches, access points, IoT devices, cameras, conference room systems, and even printers. (It's my opinion that all servers should have static IP addresses. One of the systems could have been down for an extended period of time and when another's lease was up, it grabbed the next available IP address. A patching event and subsequent reboot caused some of your systems to acquire different IP addresses. The system could have been reinstalled and a new identity generated, or perhaps someone wised up and gave static IP addresses to your server systems. Multiple things can cause this IP address musical chairs game.
Offending ECDSA key in /Users/khess/.ssh/known_hosts:4ĮCDSA host key for 192.168.1.84 has changed and you have requested strict checking.
Please contact your system administrator.Īdd correct host key in /Users/khess/.ssh/known_hosts to get rid of this message. SHA256:I02UyJs2vS0ym4jWn5upAWZDqwu5RjMg4aM9hPq8G1k. The fingerprint for the ECDSA key sent by the remote host is It is also possible that a host key has just been changed. Someone could be eavesdropping on you right now (man-in-the-middle attack)! If you've ever seen the following message, you either can freak out that someone is attempting to hack you, or you can realize that DHCP or some other anomaly has done a dirt cheap dirty deed on you: $ ssh WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY! This file will come up at some point in your career. If you didn't know about it, you should acquaint yourself now.
The offending entity is the ~/.ssh/known_hosts file. But, there's this little file in your home directory that can become a rare pain point for this ubiquitous protocol and tool. SSH is easy to use and is generally trouble-free.