How to run a Rails 3 application on localhost / <my_port>?

Question

To start the Rails application on Windows, follow these steps:

• cd <app_dir>
• rails server

I see the following:

=> Booting WEBrick => Rails 3.0.1 application starting in development on http://0.0.0.0:3000 => Call with -d to detach => Ctrl-C to shutdown server [2011-01-12 20:32:07] INFO WEBrick 1.3.1 [2011-01-12 20:32:07] INFO ruby 1.9.2 (2010-08-18) [i386-mingw32] [2011-01-12 20:32:07] INFO WEBrick::HTTPServer#start: pid=5812 port=3000 

Question 1

Why is port 3000 selected? Where is it set up?

Question 2

How can I run 2 applications in parallel? I think I need to configure one of them on a different port (for example, 3001). How can I do it?

Answer 1

Port 3000 is the default value for webrick in rails. To change the port, you can simply run rails server -p 3001 .

Run rails server -h to list all the arguments it can take.