Subdomains are a great way to organize different parts of your app. You might have an
news subdomain, etc.
constraints subdomain: 'my-subdomain' do # add routes end
Add new hosts to your development.rb configuration.
config.hosts << "my-subdomain.my-domain.local"
Add development subdomain(s) to your /etc/hosts file so it routes to your development server
Don't forget to add port 3000! You'll go this url in your browser.
CNAME record for each subdomain in your DNS configuration.
domain name and
DNS Target from Heroku.
That's it! You should be good to go.