Redirect domain’s content to another domain

1) How would I redirect user1.domain.com to display domain.com/user?id=1 content?

2) How would I redirect domain1.com to display sub.domain2.com’s content?

I have both domains on the same server/host, so I don’t think changing A records in the DNS is the issue.

The following assumes that you are using Apache.

1) How would I redirect user1.domain.com to display domain.com/user?id=1 content?

Something like the following should work although I haven’t tested it:

RewriteEngine On
RewriteCond %{HTTP_HOST}  ^user1.domain.com [NC]
RewriteRule . http://domain.com/user?id=1 [L,R]

2) How would I redirect domain1.com to display sub.domain2.com’s content?

<VirtualHost *:80>
  ServerName domain1.com
  Redirect 302 / http://sub.domain2.com/
</VirtualHost>

Check more discussion of this question.

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