Problem we are having:
A client opens an HTTPS connection to a CSM with SSL offload to SSL module. The decrypted clear HTTP request hits the IIS server and is redirected (301).
The client gets an HTTP redirect and not an HTTPS redirect.
The reason for the 301 redirect is the IIS server does not have a physical resource but rather a virtual directory so it issues a 301 and adds a /. eg https://www.cisco.com/tech is redirected to https://www.cisco.com/tech/ in a working situation.