Different back end authentication.

Hello All, I would like to know if it's possible to have more then one authenticaton backend with Freeradius. Let's say I have User1 on OpenLDAP and User2 On Microosft Windows Active Directory. I configure my device to send Authentication request (Radius) to Freeradius. User1 and User2 should be able to authentice. I was able to make it work separetly but not both at the same time Thanks for your reply.