# 1) Point *.example.com in your DNS setup to your server. # # 2) Setup an Apache vhost to catch the star pointer: # # # ServerName *.example.com # # # 3) Set the current account from the subdomain class ApplicationController < ActionController::Base before_filter :set_current_account private def set_current_account # I personally prefer "request.subdomains.last" because I see people enter # "www.subdomain.myapp.com" quite often. @current_account = Account.find_by_subdomain(request.subdomains.last) end end # 4) Tie all top-level requests off the current account class CustomersController < ApplicationController def index @customers = @current_account.customers end end