How to get update to check Feature Server
You're looking for project status url, which is a property that can be used in your module's .info file:


  Allows module maintainers to define a URL to check for updates to their module using the Update status module. No module released on drupal.org should define this parameter. URL should point to an XML feed that accepts requests in the form of http://my.domain.com/projects/{project}/{core}. In that example, project status url should be set to http://my.domain.com/projects.