yum install mod24_ssl openssl
cd letsencrypt/
./letsencrypt-auto --debug certonly --webroot -w /var/www/html/abc -d www.abc.com
Edit httpd.conf
<IfModule mod_ssl.c>
Listen 443
</IfModule>
<VirtualHost *:443>
SSLEngine on
SSLCertificateFile /etc/letsencrypt/live/www.abc.com/cert.pem
SSLCertificateKeyFile /etc/letsencrypt/live/www.abc.com/privkey.pem
SSLCertificateChainFile /etc/letsencrypt/live/www.abc.com/fullchain.pem
<Directory "/var/www/html/abc">
Options Indexes FollowSymLinks
AllowOverride All
Order allow,deny
Allow from all
</Directory>
DocumentRoot "/var/www/html/abc"
ServerName www.abc.com
</VirtualHost>
service httpd restart