I have a cloud server with only a root user. I SSH to it using RSA keys only. To make it more secure, I wanted to disable the password feature. I know that this can be done by editing the /etc/ssh/sshd_config file and changing PermitRootLogin yes to PermitRootLogin without-password. I was wondering if simply deleting the root password via passwd -d root would be the equivalent (assuming I do not create more users or new users have their passwords deleted too). Are there any security issues with one approach verses the other?