You can redirect your domain to a certain port. This depends on the WebService you are using -Nginx/Apache. If you are using Nginx, you’ll need to do add a server block to your Nginx’s website config. This can be achieved by using the bellow
Having said that, you’ll need to add it to your subdomain’s Nginx server block/config. If you are unsure how you can do that, I’ll recommend checking out he following article:
If you are using Apache, you have two options, the first one is to add a redirection rule in your website’s .htaccess and the second one would be to do it directly in the Apache’s Vhost file. I like using the first option. In your .htaccess file, you can add the following rule
# redirect to 3000 if current port is not 3000 and "some-prefix/" is matched
RewriteRule ^/(.*[^/])/?$ http://www.mysite.com:3000/$1/ [R=301,L]
If you want to use Apache’s Vhost file, I’ll recommend going through the following tutorial :
The Apache web server is the most popular way to serve web content on the internet. Apache has the ability to serve multiple domains from a single server by using a mechanism called "virtual hosts". If a virtual host is configured correctly for each domain, the web server can correctly route traffic to the appropriate files based on the domain name requested. In this guide, we'll demonstrate how to configure Apache virtual hosts on an Ubuntu 16.04 server.