Configuring Wildcard Subdomains « WordPress Codex

Configuring Wildcard Subdomains « WordPress Codex: "This page contains some examples of how to configure wildcard subdomains in different circumstances. If you cannot determine how to set up wildcard subdomains on your particular web server, contact your webhost for directions.

Contents
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1 Apache
2 CPanel
3 Plesk
4 DirectAdmin panel
5 Amazon Web Services
Apache
In the httpd.conf file, or in the include file containing the VirtualHost section for your web account, add a line like this (if it is not already present):

ServerAlias *.example.com

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