Putty fatal error Disconnected: no supported authentication methods available.

2
votes

I am connecting to a Ubuntu server via Putty and keep getting "Disconnected: no supported authentication methods available. Server refused our key." I am able to connect as ubuntu (superuser) but not as any other user. I am using Amazon web services if that helps.

3
ubuntusshamazon-web-servicesputtyssh-keys
Is your public key in the .ssh/authorized_keys files for the other users? - nandhp
Ah thanks for the input! I'll get back to you - user1789529
Yes, I have placed the public key in the .ssh/authorized_keys file using the 'vi' command and inserting the pub. key on a new line. I might just create another user and start over. Is there a straight forward article/resource anyone could recommend? - user1789529
I don't have an article to recommend, but you might check log files in /var/log and see if there are any better diagnostics from the SSH server. - nandhp

3 Answers

2
votes

Amazon actually has a guide for setting up Putty on Windows to connect to your AWS instances. It even details WinSCP for secure transfer of files. Pretty helpful guide.

http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/putty.html

1
votes

Permissions on the files in .ssh need to be restricted as well. Manpage has something on this. Also try with the logging in putty up and let us see the error from client. Also check server side /var/logs messages or syslog file.

0
votes

Look like sshd server does not accept ssh-dss public key for authentication. Just add to /etc/ssh/sshd_config key PubkeyAcceptedKeyTypes and add value ssh-dss

PubkeyAcceptedKeyTypes ssh-ed25519,[email protected],ssh-rsa,ssh-dss,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,[email protected],[email protected],[email protected],[email protected],[email protected]

to see what public keys are supported on server:

ssh -Q key