If you want to install a basic SSL certificate for free with just one click, LetsEncrypt is a great tool to use. It supports multiple domains and sub-domains, and will automatically renew itself before expiring every 90 days.
To enable LetsEncrypt in DirectAdmin, make sure you have DirectAdmin 1.50.1 or a newer version. It's recommended to set DirectAdmin to allow Server Name Indication (SNI) if you're running CentOS 6 or a newer version. This will make the setup simpler, particularly when installing SSL under an admin account on the server IP, so it won't be installed globally.
To enable LetsEncrypt, first enable the letsencrypt=1 option in the directadmin.conf file. Then, restart DirectAdmin by running the following command:
echo "action=directadmin&value=restart" >> /usr/local/directadmin/data/task.queue; /usr/local/directadmin/dataskq d2000
Next, add the /.well-known Alias by running the following command:
cd /usr/local/directadmin/custombuild
./build rewrite_confs
Finally, install the most recent version of the LetsEncrypt script by running the following commands:
cd /usr/local/directadmin/custombuild
./build update
./build letsencrypt
Once you have completed these steps, users will be able to see the LetsEncrypt option in their 'Enhanced' skin via User Level -> SSL Certificates.
