At our testing FreeSBC, we have a problem with the SSH connection. We tried to connect through- WinSCP, Putty, Cygwin, but we are ending still at „Permission denied (publickey,gssapi-keyex,gssapi-with-mic)“. Do you have some hint on how to connect to this SBC?
If the SBC is running on AWS, you will need to use the AWS key for ssh access.
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/putty.html