As a quick note, I haven’t tried to log into one of my GoDaddy websites in several months, and when I tried to log in just now I got this macOS ssh error message:
Unable to negotiate with <ip-address here> port 22: no matching host key type found. Their offer: ssh-dss
The short answer to this problem is that macOS Sierra uses OpenSSH 7, and it doesn’t use old technologies like the ssh-dss (DSA) public key algorithm. The OpenSSH “legacy technology” web page states, “It too is weak and we recommend against its use.”
MacOS/GoDaddy ssh-dss solution
If you have to use it — such as when GoDaddy controls the Linux servers — you can use this
ssh command to log into a server that uses
ssh -oHostKeyAlgorithms=+ssh-dss firstname.lastname@example.org
That solved my problem and I was able to log into my GoDaddy Linux server using ssh-dss.
For more information about this problem and the solution, see the OpenSSH legacy web page.