Autoredirect within my blog - Wordpress

I have an existing wordpress blog with some posts. But now im planning to move my blog to a sub domain. Now i want to redirect my visi开发者_高级运维tors to my sub domain.

For example if a user types

www.mysite.com/2011/07/posts.html

then he should be automatically redirected to

www.blog.mysite.com/2011/07/posts.html.

Is there any plugin to help out me? Or is there any other way?

I used this plugin to resolve my issue.

Redirection plugin