I just upgraded my MIAB box to 18.04 and 0.41. I have followed all the instructions for setting up RSA key authentication, but I can’t connect using SmarTTY or Cyberduck when I have password authentication set to no. I created the SSH key pair and while I had password authentication set to yes, I downloaded the id_rsa key file to C:\users\{myusername\.ssh. When I try to login with that key file in SmarTTY, I consistently get the message “Cannot authenticate using OpenSSH key. Login using password instead?” If password authentication is set to yes, I can, if no, I can’t.
I am using a DO droplet and I CAN log in with password from their console, but I would like to be able to use an offline SSH client. Why is this not working?
I have been using both SmartTTY and Cyberduck for a couple of years now. I WAS able to log into the previous version in both with no issues. I have other droplets on DO and I have NO issue with those so I’m not going to change software just for MIAB.
Out of curiosity, are you sending your login as root@x.x.x.x ? I’ve messed it up I can’t tell you how many times because I was using user@x.x.x.x, when DO used my key to set up a root user on the new droplet.
I finally got it to work. First I double checked the /etc/ssh/sshd_config file and commented out the line Use Pam yes. Then I deleted the existing files in /home/ubuntu/.ssh and ran ssh-keygen to get brand new keys. I then logged into SSH on SmarTTY using password and downloaded both id_rsa and id_rsa.pub files. Restarted SSH.
I am now able to log into SSH both in SmarTTY AND Cyberduck using id_rsa and passphrase. I also updated they public key on Digital Ocean in the event I want to use it again in the future.