Do MAC ID pass through dhcp relay? Even if its connected on the WAN from the internet?
So if the DHCP Server is on the WAN of the router and connected to a DHCP server on the internet is it passed?
Strictly speaking, yes. The client hardware address is a data field that will be in both the DHCPDISCOVER message (which won't leave the LAN) and the DHCPREQUEST message, which will be relayed by the relay agent.
Why do you ask?