SQL 2014 - Active Cluster DC and DR instance name same or different

Hi ,

I have 3 node cluster (Active/Active) on DC and 2 node cluster (Active/Active) on DR. 

I have installed SQL 2014 Cluster on DC with name instance suppose 'SQLTEST'. On DR I should install SQL 2014 cluster with same instance name as DC / different instance name / default Instance name.

Please suggest. 

Regards,

Nikhil P Desai