sudo yum install httpd
sudo systemctl enable httpd.service
sudo yum install mod_ssl
sudo mkdir /etc/httpd/ssl
sudo openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /etc/httpd/ssl/apache.key -out /etc/httpd/ssl/apache.crt
openssl: This is the basic command line tool for creating and managing OpenSSL certificates, keys, and other files.
req -x509: This specifies that we want to use X.509 certificate signing request (CSR) management. The "X.509" is a public key infrastructure standard that SSL and TLS adhere to for key and certificate management.
-nodes: This tells OpenSSL to skip the option to secure our certificate with a passphrase. We need Apache to be able to read the file, without user intervention, when the server starts up. A passphrase would prevent this from happening, since we would have to enter it after every restart.
-days 365: This option sets the length of time that the certificate will be considered valid. We set it for one year here.
-newkey rsa:2048: This specifies that we want to generate a new certificate and a new key at the same time. We did not create the key that is required to sign the certificate in a previous step, so we need to create it along with the certificate. The rsa:2048 portion tells it to make an RSA key that is 2048 bits long.
-keyout: This line tells OpenSSL where to place the generated private key file that we are creating.
-out: This tells OpenSSL where to place the certificate that we are creating.
Then you have to fill up like this
Country Name (2 letter code) [XX]:IN
State or Province Name (full name) []:Example
Locality Name (eg, city) [Default City]:Example
Organization Name (eg, company) [Default Company Ltd]:Example Inc
Organizational Unit Name (eg, section) []:Example Dept
Common Name (eg, your name or your server's hostname) []:example.com
Email Address []:webmaster@example.com
Then
sudo nano /etc/httpd/conf.d/ssl.conf
Find the section that begins with . We need to make a few changes here to ensure that our SSL certificate is correctly applied to our site.
First, uncomment the DocumentRoot line and edit the address in quotes to the location of your site's document root. By default, this will be in /var/www/html, and you don't need to change this line if you have not changed the document root for your site. However, if you followed a guide like our Apache virtual hosts setup guide, your site's document root may be different.
DocumentRoot "/var/www/example.com/public_html"
Next, uncomment the ServerName line and replace www.example.com with your domain name or server IP address (whichever one you put as the common name in your certificate):
ServerName www.example.com:443
Find the SSLCertificateFile and SSLCertificateKeyFile lines and change them to the directory we made at /etc/httpd/ssl:
SSLCertificateFile /etc/httpd/ssl/apache.crt
SSLCertificateKeyFile /etc/httpd/ssl/apache.key
sudo apachectl restart
sudo apachectl restart
Source:https://www.digitalocean.com/community/tutorials/how-to-create-an-ssl-certificate-on-apache-for-centos-7
