Your network contains two servers named Server1 and Server2 that run Windows Server 2012 R2.  Server1 is a DHCP server that is configured to have a scope named Scope1. Server2 is configured to obtain an IP address automatically. In Scope1， you create a reservation named Res_Server2 for Server2. A technician replaces the network adapter on Server2. You need to ensure that Server2 can obtain the same IP address.  What should you modify on Server1？（）