Dave said: "The only reason for this I can fathom is because the DHCP request is no longer a broadcast it now has the source address of the router interface that the helper address is setup on and it seems DHCP will take this into account when dishing out addresses."
That's exactly the assumption I've always made, but I'm not totally convinced. I'd like to sniff the packet and actually see whether it's dependant upon the source address or something contained within the packet. As per usual IF I get chance I'll put a sniffer on. Anybody know for sure? Gaz wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > As mentioned in an earier reply..you must have your DHCP Scopes correctly > set up > > I've found that with NT4/W2k DHCP servers > that, If for example your DHCP server is set up to dish out addresses in the > range of 192.168.1.1 to 100 mask 255.255.255.0 and it receives a request for > an address directed from the helper routers interface which has an address > of 10.1.1.1 (which means your DHCP clients will be on the same network) it > will ignore that request. > The only reason for this I can fathom is because the DHCP request is no > longer a broadcast it now has the source address of the router interface > that the helper address is setup on and it seems DHCP will take this into > account when dishing out addresses. > > I've found that if a scope in the 10.1.1.0 range is setup on the server my > DHCP clients will recieve an IP address in the correct 10. range with no > problem. > > I have two scopes on my DHCP server > 172.16.60.1 - 172.16.61.254 Subnet 255.255.254.0 and 10.222.36.1 > -10.222.37.254 Subnet 255.255.254.0 > > my router interface configured to forward DHCP reqests is set up as follows > .. > ip address 10.222.36.2 255.255.254.0 > ip helper-address 155.131.60.40 (MY DHCP SERVER address ) > my DHCP clients never get an address from the wrong range if i disable the > 10.222.36.0 range > my dhcp clients behind the router don't get an address at all ... > > Hope this make sense and helps and if i'm talking pants please someone put > me straight > ... > > Regards Dave Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=27441&t=27380 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
