Search notes:

ssh-keyscan

ssh-keyscan gathers public keys from servers.

This command was designed to aid in building known host files.

No login access is required on the servers that the tool is scanning. The tool does not employ encryption either (and is therefore subject to man-in-the-middle attacks).

Examples etc.

Get the public rsa key from server srv.xy, using port 2121 (without -p, the default port 22 would be used):

$ ssh-keyscan -p 2121 -t rsa srv.xy

The output of ssh-keyscan can be piped into ssh-keygen:

$ ssh-keyscan -p 2121 -t rsa srv.xy | ssh-keygen -lv -f -

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