Just some quick points about DHCP
Okay, so everybody knows DHCP pretty well.I just want to point out a few little details as background for a future post:
DHCP Relays Can Change Things
The first point is about those times when the DHCP client and server aren't on the same segment.
In these cases, a DHCP relay (usually running on a router) scoops up the helpless client's broadcast packets and fires them at the far away DHCP server. The server's replies are sent back to the relay, and the relay transmits them onto the client subnet.
The DHCP relay can change several things when relaying these packets:
- It increments the bootp hop counter.
- It populates the relay agent field in the bootp header (The DHCP server uses this to identify the subnet where the client is looking for a lease).
- It can introduce additional DHCP options to the request.