Hana DB switch for DR setup

Hello Experts,

I have a few questions related to the HANA DR setup.

In our landscape the HANA Primary and Secondary instance was not installed using any Virtual hostname. I understand that to be able to switch to the secondary site all we need to do is perform a take over and stop replication on the Primary. My question here is how do we make the application server connect to the Secondary Hana DB. Changing only the SAPDBHOST parameters in the DEFAULT.PFL will not help.Please let me know what else needs to be changed.

Regards,

Raj