In most case,
I’m installing LetsEncrypt ssl with webmin menu.
It’s included Webmin Configuration menu -> SSL-Encryption sub menu
And , You can choose LetsEncrypt page.
And, "Request Certificate" Some Seconds Later , you will get Let's Encrypt SSL. SSL Cert are made 3 files. You can identify SSL Settings Page:: 1. /etc/webmin/letsencrypt-key.pem 2. /etc/webmin/letsencrypt-cert.pem 3. /etc/webmin/letsencrypt-ca.pem And You can Identify this ssl makes well informations. in current Certificate files. And You Can check Your SSL Validity. Next you can copy this SSL to your Proper nginx cert directory. in my case vhost.conf , /etc/nginx/sites-available/ssl/ directory i use. > ssl on; > ssl_certificate /etc/nginx/sites-available/ssl/xxx.xxxrustfarm.io.cert; > ssl_certificate_key /etc/nginx/sites-available/ssl/dev.xxxrustfarm.io.key; and , > cp /etc/webmin/letsencrypt-key.pem /etc/nginx/sites-available/ssl/xxx.xxxrustfarm.io.key make chained certification > cat /etc/webmin/letsencrypt-cert.pem /etc/webmin/letsencrypt-ca.pem > /etc/nginx/sites-available/ssl/dev.xxxrustfarm.io.cert And You can renewal before Mar 17 , it's depend on your case. ** Important things are concate cert and ca files to cert , in case of nginx , and apache. Have a good LetsEncrypt SSL.