Author: James Courtier-Dutton Date: To: Hampshire LUG Discussion List Subject: Re: [Hampshire] [OT] Windows 2003 Server DHCP not responding to
requests from same VLAN
On 22 January 2010 17:08, Tony Whitmore <tony@???> wrote: >
> We have a Windows 2003 Server running as a DHCP server at work. (I know, I
> know!) The network is divided into two VLANs, with a frame switch
> configured to act as a DHCP relay between the two VLANs. Consequently
> requests for IP addresses made by clients on VLAN 2 are relayed to the DHCP
> server on VLAN 1 and a valid address returned from the pool available for
> the subnet associated with IP address of the DHCP relay in the VLAN.
>
> However, the server doesn't respond to DHCP requests from VLAN 1, the VLAN
> on which it resides. I have installed Wireshark (see, FLOSS gets a look
> in!) and it shows the DHCP request packets arriving at the server OK. There
> is no response sent out, however, despite there being a valid DHCP range
> configured.
>
> What I can't figure out is if there are additional configuration options
> within Windows 2003 DHCP server which restrict which IP address range(s)
> are available to which VLAN. The server only has one IP address/network
> interface and the DHCP server is listening on that interface. Has anyone
> got any tips?
>
> Tony
>
The ethernet IP address of the DHCP server has to be in the same
subnet as the IP addresses being given out.
So check that your VLAN1 scope is in the same subnet as you DHCP
servers's ip address.
The only exception to this is if the DHCP requests are going via a
DHCP/BOOTP relay.
