Question
MITM: The authenticity of host can't be established.
Hi,
I’ve searched through the questions and am surprised that I haven’t seen an adequate answer to this question yet so maybe I’m missing something.
I created a new Ubuntu droplet and when I try to SSH into it I’m presented with the following warning:
The authenticity of host 'x.x.x.x' can't be established.
ECDSA key fingerprint is SHA256:XwYwckT3ivmDkwGBBRN93ANuzYpvlEvo4DQ+qZo7MB8.
Are you sure you want to continue connecting (yes/no)?
SSH is warning me that there could be a man-in-the-middle attack occurring (thank you SSH!). In order to avoid this I need to verify the fingerprint of my new droplet through a secure channel (i.e., the DigitalOcean web interface). The only promising option I see in the web interface is the Console, which I presume will allow me to log in and view the server logs where I can see the server fingerprint. However, I can’t log in through the console because I added an SSH key to my droplet at creation time and no password was set.
Does this mean that I have to forgo the security of adding an SSH key at droplet creation time so that I can log in via the console to verify my server fingerprint, and then after that add a SSH key manually? It’s considered bad practice to rely on passwords without SSH keys these days so this surprises me.
Thanks for your help in keeping my droplets secure from man-in-the-middle and password attacks.
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