Hot to get the RSA key of your server

ssh-keyscan -t rsa YOUR_SERVERs_IP_ADDRESS_OR_HOSTNAME

Output:

# YOUR_SERVERs_IP_ADDRESS_OR_HOSTNAME:22 SSH-2.0-OpenSSH_5.3
YOUR_SERVERs_IP_ADDRESS_OR_HOSTNAME ssh-rsa AAAAB3NzaC1yc...

Check with the several type of the keys:

ssh-keyscan -t rsa1,rsa,dsa,ecdsa,ed25519 YOUR_SERVERs_IP_ADDRESS_OR_HOSTNAME
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