.htaccess Redirect of old post links


I’m currently trying to migrate a WordPress site and want to make sure all of the old post URLs out there still work.

The client has their WordPress blog setup in a subdirectory, http://example.com/blog on a Dedicated Server

The recently purchased a WordPress Managed server to host their primary site, http://example.com

We are now needing to move the blog access URL from “/blog” to a subdomain, blog.example.com.

What type of redirect do I need to put in the .htaccess file so that http://example.com/blog & all associated posts and pages point over to http://blog.example.com?

Example when someone visits the old URL of http://example.com/blog/post it redirects them to http://blog.example.com/post

Thanks for the help!