./letsencrypt-auto --help

"sudo" is not available, will use "su" for installation steps...
Sorry, I don't know how to bootstrap Certbot on your operating system!
You will need to bootstrap, configure virtualenv, and run pip install manually.
Please see https://letsencrypt.readthedocs.org/en/latest/contributing.html#prerequisites
for more info.

Linux version 2.6.32-673.8.1.lve1.4.3.el6.x86_64 (mockbuild@build.cloudlinux.com)
(gcc version 4.4.7 20120313 (Red Hat 4.4.7-16) (GCC) ) #1 SMP Wed Feb 10 08:57:30 EST 2016