Free Online Tutorials

Use this command:

./certbot-auto certonly -d yourdomain.com

Result:

[root@tutorialspots ~]# ./certbot-auto certonly -d wss.tutorialspots.com
Saving debug log to /var/log/letsencrypt/letsencrypt.log

How would you like to authenticate with the ACME CA?
-------------------------------------------------------------------------------
1: Apache Web Server plugin - Beta (apache)
2: Nginx Web Server plugin - Alpha (nginx)
3: Spin up a temporary webserver (standalone)
4: Place files in webroot directory (webroot)
-------------------------------------------------------------------------------
Select the appropriate number [1-4] then [enter] (press 'c' to cancel): 2
Plugins selected: Authenticator nginx, Installer None
Obtaining a new certificate
Performing the following challenges:
http-01 challenge for wss.tutorialspots.com
Waiting for verification...
Cleaning up challenges

IMPORTANT NOTES:
 - Congratulations! Your certificate and chain have been saved at:
   /etc/letsencrypt/live/wss.tutorialspots.com-0001/fullchain.pem
   Your key file has been saved at:
   /etc/letsencrypt/live/wss.tutorialspots.com-0001/privkey.pem
   Your cert will expire on 2018-06-23. To obtain a new or tweaked
   version of this certificate in the future, simply run certbot-auto
   again. To non-interactively renew *all* of your certificates, run
   "certbot-auto renew"
 - If you like Certbot, please consider supporting our work by:

   Donating to ISRG / Let's Encrypt:   https://letsencrypt.org/donate
   Donating to EFF:                    https://eff.org/donate-le