Nginx Redirects For “non-www” Sub-domains To “www”

Introduction

When you visit https://vultr.com, you’ll notice it automatically forwards you to its “www” subdomain http://www.vultr.com. This writeup shows you how to setup Nginx to redirect a non-www sub-domain to a “www” one, and vice-versa.

Pre-requisites

• You have a Vultr Linux instance running Nginx.
• Your have domain name (e.g example.com) whose DNS A records for “@” and “www” are pointing to the IP of your Vultr machine above.

Setup to redirect “non-www” to “www”

Method 1: For a single domain

Add an additional server block to your vhost setting so it looks similar to below:

server {
    listen 80;
    server_name example.com;
    return 301 $scheme://www.example.com$request_uri;
}

server {
    listen 80;
    server_name www.example.com;

    #other site settings go here (e.g. logs, site root)
}

Method 2: For all domains

Add below snippet within the http directive in your nginx.conf file (usually located in /etc/nginx in Ubuntu/Debian systems)

server {
    server_name "~^(?!www/.).*" ;
    return 301 $scheme://www.$host$request_uri;
}

Setup to redirect “www” to “non-www”

Method 1: For a single domain

Add an additional server block to your vhost setting so it looks similar to below:

server {
    listen 80;
    server_name www.example.com;
    return 301 $scheme://example.com$request_uri;
}

server {
    listen 80;
    server_name example.com;

    #other site settings go here (e.g. logs, site root)
}

Method 2: For all domains

Add below snippet within the http directive in your nginx.conf file (usually located in /etc/nginx in Ubuntu/Debian systems)

server {
    server_name "~^www/.(.*)$" ;
    return 301 $scheme://$1$request_uri ;
}

Written by Lami Adabonyan