Apache Configuration with Proxy in RHEL 7 / CentOS 7

Apache Web Server (httpd) in RHEL and CentOS are similar.

$ yum install httpd mod_proxy mod_ssl mod_proxy_html mod_rewrite  -y

httpd : httpd daemon install http server (web) apache

mod_proxy : This library usually comes by default. This helps for proxy setup (Forward / reverse) 

mod_ssl : This library helps for HTTPS connection support in mod_proxy (proxy) to do for HTTPS as well

mod_proxy_html : This library supports for rewrite rule to support html, images and other content loading in apache

mod_rewrite : This library helps for rewrite rule in apache configuration.

$ grep 'mod_proxy' /etc/httpd/conf.modules.d/00-proxy.conf

Above command will show you already the mod proxy libaries loaded (LoadModule) in apache (httpd) and in the same configuration you will see for ssl (LoadModule configuration) in different *.conf

In order for apache to achieve forward and reverse proxy create below configuration. 

Create reverse-proxy.conf file or your own file naming file and have the below configuration.

$ vi /etc/httpd/conf.d/reverse-proxy.conf

        # Below fields helps on forward proxy request and proxy time out

        ProxyRequests On

        ProxyVia On

        ProxyTimeout 60

# Below field helps to turn on HTTPS configurations (reverse / forward)

        SSLProxyEngine On

# Proxy servers permissions

       

                Require all granted

       

# Specify Forward proxy remote servers

        ProxyRemote "http" "http://proxy.ebiz.abccompany.com:80"

        ProxyRemote "https" "http://proxy.ebiz.abccompany.com:80"

# Specify no proxy servers

        NoProxy ".abccompany.com"

# Reverse proxy urls and connectiontimeout happens when there is no response from the url

        ProxyPass /foo http://www.webreference.com/html/tutorial2/2.html connectiontimeout=5

        ProxyPassReverse /foo http://www.webreference.com/html/tutorial2/2.html

        ProxyPass /bar https://vzweb2.abccompany.com connectiontimeout=5

        ProxyPassReverse /bar https://vzweb2.abccompany.com

        ProxyPass /geek https://www.ssllabs.com/ connectiontimeout=5

        ProxyPassReverse /geek https://www.ssllabs.com/

Restart 'service httpd restart' after configuration changes. 

You can add environment variables in file '/etc/sysconfig/httpd' if required.

Test it with :        curl http://localhost/foo

   curl http://localhost/bar

Best Article to know about forward-reverse proxy :

https://geekpeek.net/forward-reverse-apache-proxy-centos/ (The best forward and reverse proxy)

Reverse proxy well explained video link : https://www.youtube.com/watch?v=MQMIhAbPzb4