In the past we have had many non domain joined Windows clients that were unable to contact our Policy Manager server so they have to reach out to the web to get virus definitions. We were wondering if Mac clients work the same way?
Could you please clarify what do you mean by "non-domain joined" term used here. If you are referring to the mac clients in a different domain than PMS, it depends whether the client could connect to the PMS or not. If PMS is reachable, then mac client should be able to connect to the PMS to get the virus definitions. If PMS is not reachable, then Mac client will connect to our backend server for the latest virus definitions.
Please check the client connectivity status. For our database updates to be done via PMS, a successful client connection to PMS is needed. As long as Mac client can actually connect to PMS, it should be fine to get the latest virus definitions updates from PMS.