Error “Server refused our key”

I recently got the "Server refused our key" error while configuring a VPS. After a lot of trial and error, I solved it.

My problem happened on an Ubuntu 22 LTS VPS. The key was configured in the cloud, I selected it to load with the VPS, and everything should have worked, but it did not. This link has some information about the problem.

These were the tests I ran while accessing SSH through the hosting provider's web console:

1. I applied permissions to the profile's .ssh folder and the authorized_keys file.

chmod 700 ~/.ssh chmod 600 ~/.authorized_keys

2. I checked whether the configuration file had the correct parameters to allow access.

nano /etc/ssh/sshd_config

I made several attempts, but here is what solved the problem and a few tips in case you have a similar issue. Edit the file above and use these parameters:

LogLevel DEBUG3 PermitRootLogin yes PubkeyAuthentication yes PubkeyAcceptedKeyTypes=+ssh-rsa AuthorizedKeysFile .ssh/authorized_keys .ssh/authorized_keys2 PasswordAuthentication no

Tip: always check whether any of the lines above are commented with #. If they are, remove the comment.

After making the changes, restart the service and try connecting again. Use the command below to restart it:

sudo service sshd restart

If that does not solve it, then the issue needs to be analyzed in the log with:

tail -vF /var/log/auth.log