How to redirect subdomain to a sub folder/directory using Nginx?

In this tutorial, we will explain how to use nginx to redirect a subdomain to a subdirectory. This practice can be helpful to prevent broken links and maintain SEO, you must redirect a subdomain to a subdirectory when moving it to a subfolder on your website.

How to redirect a domain to a subdirectory in nginx server?

For demonstration we are going to redirect app.domain.com to /app sub-directory.

Create the configuration file for the domain in sites-available (or sites-enabled) sub-directory of nginx configuration directory i.e. /etc/nginx/sites-available/app.domain.com.conf.

$ sudo vim /etc/nginx/sites-available/app.domain.com.conf

Two different methods to send a user to different domain:

URL string and subdomain will be permanently redirected to the subdirectory. Use one of these methods and put these lines in the configuration file.

Method 1: Using rewrite.

server {
  listen 80;
  server_name app.domain.com www.app.domain.com;
  rewrite ^ http://domain.com/app/$request_uri? permanent;
}

Method 2(recommended): for nginx version 0.9.1 or higher. Using return with status code 301(Moved permanently) or 302 (found).

server {
  listen 80;
  server_name app.domain.com www.app.domain.com;
  return 301 http://www.domain.com/app/$request_uri;
}

Replace app.domain.com and domain.com/app/ with your subdomain and subdirectory in the code above. All of the queries made to your website's app.domain.com will be redirected to domain.com/app/. After the subdomain name in the requested URL $request_uri(URL stub after subdomain name). We issue a 301 redirection code in our response.

Finally, You can save and exit the file.

Verify our configuration, then launch Nginx.

It is a recommended practice to test new configurations before loading them to the production server because a single syntax mistake will prevent the Nginx service from running, which will prevent users from accessing your website. You can use the following command to do so.

$ sudo nginx -t -c /etc/nginx/sites-available/app.domain.com.conf

Enable the site if no issues were discovered. In order to accomplish this, we must build a symbolic link between the site configuration file and the sites-enabled directory using the following command:

$ sudo ln -s /etc/nginx/sites-available/app.domain.com.conf /etc/nginx/sites-enabled/app.domain.com.conf

Finally, Start/Restart/Reload the server to load the changes:

$ sudo systemctl restart nginx

or

$ sudo service nginx restart