Prober Pools in GTM

Understood David, there is no LTM platform in the DC's this new Generic host will be configured. Out of 2 DC's with GTM's, one DC is primary and the other is Dr only. I would want DR GTM monitor this generic host only if GTM in primary DC fail.

I use Layer 7 HTTP monitor to check the health of the VS on the server, and I think with that monitor GTM would check the availability of the service externally so if the primary DC cannot reach the url then Primary GTM should fail the traffic to DR GTM (provided it could reach the url externally).

So since both GTM's are in remote DC's, do I really need a prober at all? Thanks