SSH Permission denied (publickey,gssapi-keyex,gssapi-with-mic) | non-root user
Be sure to restart sshd after you've made changes to /etc/ssh/sshd_config.
The problem I had was that my key was of 4096 bits size and was not acceptable. I created a 2048 bits key and it worked!
ssh-keygen -t rsa -b 2048 -C "<email>"