What are your objectives from this DR testing ?
What are the front-end application's protocols using the 'Prod' volumes for?
Hopefully, you have all infrastructure (network/VLAN/hypervisor) in place to point the "clients" to DR volume (If disaster occurs and you happen to loose Prod site).
In any case, this is a very basic and yet well defined guide on DR testing.
Guidelines for SnapMirror Disaster Recovery (DR) testing and reverse SnapMirror in ONTAP:
https://kb.netapp.com/Advice_and_Troubleshooting/Data_Protection_and_Security/SnapMirror/Guidelines_for_SnapMirror_Disaster_Recovery_(DR)_testing_and_...
Further, there is plenty of stuff around this on : NetAp KB & Documentation site, so just look up.