Eu já configurei o login sem senha para localhost via ssh e ele funciona.
justinwu@ubuntu:~$ ssh root@localhost
Welcome to Ubuntu 14.04.5 LTS (GNU/Linux 3.13.0-110-generic x86_64)
* Documentation: https://help.ubuntu.com/
2 packages can be updated.
0 updates are security updates.
New release '16.04.2 LTS' available.
Run 'do-release-upgrade' to upgrade to it.
Last login: Tue Mar 7 10:08:22 2017 from localhost
Mas enquanto executa um script e precisa logar como root via ssh, ele retorna o erro 'Permission denied (publickey)'.
Starting tests: Tue Mar 7 10:08:28 2017
Launching 20 processes.
Starting test client: 0 Host: localhost Workload: VDI Workdir: /mnt/share
Permission denied (publickey).
Deve funcionar, mas não tenho certeza porque é negado.