Cacher is the code snippet organizer for pro developers

<?php
/* User Login Redirect to Dashboard */
function login_site_redirect ( $redirect_to ) {
	global $user;
	$primary_blog_id = get_usermeta($user->ID, 'primary_blog');
	$blog_details = get_blog_details($primary_blog_id);
	$redirect_url = $blog_details->siteurl . "/wp-admin/";
	return $redirect_url;
}
add_filter ( 'login_redirect', 'login_site_redirect', 10, 3 ); 
?>