I would like to use both web server and appserver for WordPress so that Appserver and db server should comes under private network. Since WordPress has only apache please let me know the communication between app and webserver?

Detailed Explanation

We are deploying a WordPress site on a 3 tier architecture, meaning... Tier 1 - a web server (just to get the request and send back to app server) Tier 2 - App server (this is where WordPress is actually deployed. But will be in a private network for security reasons) Tier 3 - DB server. Our initial problem is that when a page is browsed using the web server IP, it renders web the page. But inside the content, you'll be able to see the app server IP. Similarly the js/css files are also loading from app server IP. This is b'cos the site URL in options table is the app server IP. WordPress is not allowing us to put the webserver IP in the site URL, as it expected to mention only the IP where it resides / deployed. THis you can understand i hope. Pls let us know if there is a way to fix it. 2ndly, we are planning to deploy a load balancer and have 2 app servers but the database will be one and same for both the app servers. When the database has IP of app server 1 as the site URL, how it will be work when the load balancer call the app server 2? pls let me know if i need to rephrase or elaborate my above questions further?