Dns add www prefix? [duplicate]

问题

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Closed 7 years ago.

Possible Duplicate:
apache redirect from non www to www

Is it possible to configure DNS to add www. prefix to the domain name?

Here is an example of this

回答1:

Nope. You have to configure the webserver at yourdomain.com to redirect to www.yourdomain.com.

For example, on apache, you can use this configuration (using mod_alias):

<VirtualHost *:80>
  ServerName www.yourdomain.com
  ## Actual configuration here...
</VirtualHost>

<VirtualHost *:80>
  ## redirect non-www to www
  ServerName www.yourdomain.com
  ServerAlias yourdomain.com

  RedirectMatch permanent ^(.*) http://www.yourdomain.com$1
</VirtualHost>

回答2:

1. You should add a NS A entry to the DNS record for both normalurl.com and www.normalurl.com
2. Enable mod_rewrite on Apache and create a .htaccess file with the following entries:

RewriteEngine On

RewriteCond %{HTTP_HOST} !^www.normalurl.com$ [NC]
RewriteRule ^(.*)$      http://www.normalurl.com/$1 [L,R]

回答3:

A DNS response contains a mapping of a domain name to an IP address. While you could alias example.net to www.example.net with a CNAME record, this would not be visible for the user.

Most likely, you want to configure your web server to send an HTTP 301 redirect to the correct URL.

来源：https://stackoverflow.com/questions/8624663/dns-add-www-prefix