Friday, July 29, 2011

Difference between Application server and Web Server

apache, nginx, IIS are web servers
mongrel, webrick, phusion passenger are app servers

App server is something which works with particular programming language and parses and executes the code
since mongrel and webrick can only work with rails, so they are app servers

Web servers are servers which can take the request from the browser.
Web servers normally works on port 80 though we can change the port in configuration
since mongrel and webrick can take that request directly, so they can be thought of as web servers but web servers do have a lot of other functionality like request pipeline, load balancing etc.
App servers lack these functionalities.

About Mongrel server:
mongrel work as web as well as app server if you are talking about dev environment
but in production, mongrel alone can not work it will be too slow
so we need a web server in front of mongrel

Thanks to Mr. Sumit  Garg & Mr. Sidhant for clarifying these points in details.
I would love to have others view also on this.


  1. Thanks for the crisp and to the point explanation.

  2. Nice post . . Very Useful information provid interview question and answer for all company.

  3. Hi Ritesh,

    As per my understanding Mongrel is a Web Sever.

    As the server which supports HTTP requests are web servers.