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Today, we will show you, How to install Let’s Encrypt on CentOS 7 with Apache. Let’s Encrypt is a completely free and automated, new certificate authority developed by the Internet Security Research Group (ISRG) and recognized by all major browsers. They make it a breeze to set up TLS certificates for your web server. And for free! Let’s Encrypt is supported by major players like Mozilla, Akamai, Cisco, the EFF and managed by the Linux Foundation. Let’s Encrypt provides free, automatic and secure certificates. The website owners can easily obtain security certificates within minutes, enabling a safer web experience for all.In today’s tutorial we are going to learn how to install a Let’s Encrypt SSL certificate on CentOS 7 with Apache, and configure the certbot for automatic renewal.

1. Update the system

As usual make sure the system is fully up to date before installing any packages:

# yum -y update

2. Install Apache

We are going to use Apache as our web server, install it using this command:

# yum -y install httpd

3. Install mod_ssl

Install mod_ssl as well as we are going to need it to configure our Let’s Encrypt SSL certificate:

# yum -y install mod_ssl

4. Configure Apache

Create a document root folder for your site:

# mkdir /var/www/test

Create a virtual host config file for your site by opening it with nano and then pasting the following contents inside:

# nano /etc/httpd/conf.d/test-site.conf

<VirtualHost *:80>
    ServerAdmin admin@test.com
    DocumentRoot "/var/www/test"
    ServerName test.com
    ServerAlias www.test.com
    ErrorLog "/var/log/httpd/test.error_log"
    CustomLog "/var/log/httpd/test.access_log" common
</VirtualHost>

Add a index.html file for testing purposes later with the following contents:

# nano /var/www/test/index.html

It works!

Change owner of the “/var/www/test” directory to the apache user so Apache can read the directory:

# chown -R apache:apache /var/www/test

Remember to change “test” for your site’s name.
Now that we have Apache installed we can continue by installing certbot.

5. Install certbot

To install certbot first we need to make sure we have the EPEL repository enabled, to do that execute the following command:

# yum -y install epel-release

Make sure yum-utils is installed:

# yum -y install yum-utils

Then install certbot for Apache:

# yum -y install certbot-apache

Now that we have certbot installed, run certbot with the following command:

# certbot-apache

Certbot will ask you for the names you would like to activate HTTPS for:

Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator apache, Installer apache
Starting new HTTPS connection (1): acme-v01.api.letsencrypt.org

Which names would you like to activate HTTPS for?
-------------------------------------------------------------------------------
1: test.com
2: www.test.com
-------------------------------------------------------------------------------
Select the appropriate numbers separated by commas and/or spaces, or leave input
blank to select all options shown (Enter 'c' to cancel):

Press enter to continue and then optionally if you want you can redirect your sites to HTTPS:

Please choose whether or not to redirect HTTP traffic to HTTPS, removing HTTP access.
-------------------------------------------------------------------------------
1: No redirect - Make no further changes to the webserver configuration.
2: Redirect - Make all requests redirect to secure HTTPS access. Choose this for
new sites, or if you're confident your site works on HTTPS. You can undo this
change by editing your web server's configuration.
-------------------------------------------------------------------------------
Select the appropriate number [1-2] then [enter] (press 'c' to cancel):

If everything goes well you should see the following output:

-------------------------------------------------------------------------------
Congratulations! You have successfully enabled
https://test.com and https://www.test.com

You should test your configuration at:
https://www.ssllabs.com/ssltest/analyze.html?d=test.com
https://www.ssllabs.com/ssltest/analyze.html?d=www.test.com
-------------------------------------------------------------------------------

6. Configure automatic renewal

Now we are going to add a cronjob so our Let’s Encrypt SSL certificates can be renewed automatically.

First run the following command so we can have nano as the default editor:

# export EDITOR=/bin/nano

Then execute the following command to edit the crontab:

# crontab -e

Let’s Encrypt recommends the automatic renew cronjob to run twice a day, to do that add the following line and then save and exit the crontab:

* */12 * * * /usr/bin/certbot renew >/dev/null 2>&1

Now you should have successfully installed and configured Let’s Encrypt with Apache.