1. Run these commands on the existing DHCP server (currently Windows Server 2003)
net stop dhcpserver
cd %systemroot%\system32\dhcp
jetpack dhcp.mdb temp.mdb
netsh dhcp server export C:\dhcp.txt all

2. Import the dhcp database onto the new server
Copy the dhcp.txt file from the original server onto new server's c:\ drive
Run these shell commands:
Import-Module ServerManager
Add-WindowsFeature -IncludeManagementTools dhcp
Add-DhcpServerInDC dhcpservername dhcpipaddress
netsh dhcp server import c:\dhcp.txt all
restart-service dhcp -force

3. Test to see if the new server now assume the DHCP role by running these commands on a workstation with DHCP enabled
ipconfig/release
ipconfig/renew
ipconfig /all | find /i "DHCP Server"