I won’t dare mention how much time I spent last night trying to debug the following error on a server that was previously working – but I did manage to get through the last two episodes of “Sons of Anarchy” on Netflix.

“Disconnected: No supported authentication methods available (server sent: publickey)”

As soon as you enter the username the session returns immediately without prompting for the password.

I initially started looking at the local SSH configuration – which was fruitless.

It took one of my networking colleagues all of 5 minutes to see the issue when looking at the traffic on the switches. An alternative option would be to use tcpdump as outlined in earlier blogs.

Solution : There was a duplicate ip address on the network from a previously built system.