What's wrong with this rewrite rule (redirect a directory request to another server)?

I'm try to redirect any request to mydomain.com/video/(.*) to video.mydomain.com/$1. I have the following rule:

RewriteRule ^video/(.*)$  http://video.mydomain.com/$1 [R=301,L]

But it doesn't seem to work. Instead it follows an additional r开发者_如何学编程ewrite rule which I have later which redirects all requests to index.php.

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Not a direct answer to the question, but there is a simpler way to do this without mod_rewrite:

Redirect permanent /video http://video.mydomain.com/

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You forgot one slash after the start anchor:

RewriteRule ^/video/(.*)$  http://video.mydomain.com/$1 [R=301,L]