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# forward from domain aliases
RewriteEngine On
RewriteCond %{HTTP_HOST} ^(www.)?domain1.com [NC,OR]
RewriteCond %{HTTP_HOST} ^(www.)?domain2.com [NC,OR]
RewriteCond %{HTTP_HOST} ^(www.)?domain3.com [NC,OR]
RewriteCond %{HTTP_HOST} ^(www.)?and_so_on.com [NC]
RewriteRule (.*) <a href="http://maindomain.com/$1" >http://maindomain.com/$1</a> [R=301,L]
# END forward from domain aliases

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