LetsEncrypt is a free SSL tool that lets you install a very basic free SSL Certificate with 1 click. It supports multiple domains and sub-domains, and will auto-renew automatically before it expires after it’s ~90 day lifespan.

To enable this feature in DirectAdmin, ensure you have DirectAdmin 1.50.1 or newer.

If you’re running CentOS 6 or newer, it’s recommended to set DA to allow SNI. This will keep the setup simpler, especially when setting up SSL under an Admin account on the server IP (so it’s not installed globally)
Enable the letsencrypt=1 option in the directadmin.conf
Restart DirectAdmin:
echo “action=directadmin&value=restart” >> /usr/local/directadmin/data/task.queue; /usr/local/directadmin/dataskq d2000
Add the /.well-known Alias:
cd /usr/local/directadmin/custombuild
./build rewrite_confs
Install the most recent version of the script:
cd /usr/local/directadmin/custombuild
./build update
./build letsencrypt
Users should then be able to see the LetsEncrypt option in their ‘Enhanced’ skin via:

User Level -> SSL Certificates