Subject: Re: dhcpd(8) _cannot_ be completely disabled on an interface
To: Andrew Brown , Dennis Ferguson <>
From: John Nemeth <>
List: tech-net
Date: 01/09/2002 19:16:06
On May 30,  1:41pm, Andrew Brown wrote:
} i was merely expecting that i'd be allowed to give out addresses from
} another logical network on the same physical network...hmm...yeah.
} that didn't work.  i wonder...

     When a client first starts up, it doesn't have an IP address
therefore the concept of logical network doesn't exist.  It starts by
broadcasting an DHCPDISCOVER packet which will reach all DHCP servers
(or relay agents) on the same physical network.  A DHCP server can hand
the client any IP address that will work on the physical network
(provided the address is available of course).  It is also responsible
for handing the client the proper netmask to go with the IP address.
Only at this point does the client gain the concept of a logical
network.  The server also needs to give the client a gateway address if
it wants the client to be able to reach machines on other
logical/physical networks.

}-- End of excerpt from Andrew Brown