Membership in the local Administrators group, or equivalent, is the minimum required to complete this procedure. first we have to install RRAS from server mgr >> add roles. and install it. Open the Routing and Remote Access MMC snap-in. In the console tree, expand the server name, and then expand IPv4. Under IPv4, right-click General, and then select New Routing Protocol. Select DHCP Relay Agent, and then click OK. Right-click DHCP Relay Agent, and then select New Interface....