DHCP address leasing

If there is only one DHCP server for a network how does it know what
ip addresses to give to what subnets? not taking into account the
scopes that can be used. In other words how can the dhcp server lease
out ip addresses without a scope and do this acroos the whole network.
This maybe a simple question but hey.

This article explains:

120932 DHCP: Spanning Multiple Subnets
http://support.microsoft.com/?id=120932

--

Thanks,
Marc Reynolds
Microsoft Technical Support

This posting is provided "AS IS" with no warranties, and confers no rights.


"Nathan" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) om...
> If there is only one DHCP server for a network how does it know what
> ip addresses to give to what subnets? not taking into account the
> scopes that can be used. In other words how can the dhcp server lease
> out ip addresses without a scope and do this acroos the whole network.
> This maybe a simple question but hey.

Marc thanks for the reply, article was good. but if one has only one
DHCP server and multiple subnets, with out using a scope is there a
way for the dhcp server to assign ip's? how would the dhcp server know
which ip's to assign?

thank you once again.

Without a scope, DHCP can not assign any IP.
What is that you wish to do, or if any what problem
are you facing?

Sharad
"Nathan" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) om...
> Marc thanks for the reply, article was good. but if one has only one
> DHCP server and multiple subnets, with out using a scope is there a
> way for the dhcp server to assign ip's? how would the dhcp server know
> which ip's to assign?
>
> thank you once again.

As Sharad states you need a scope for DHCP to be able to assign IP
addresses. If you have multiple subnets and one DHCP server you can create
scopes for each subnet on the DHCP server and configure your routers to do
bootp or DHCP relay. The process is described in this article:

120932 DHCP: Spanning Multiple Subnets
http://support.microsoft.com/?id=120932

"A relay agent that conforms to RFC 1542 relays DHCP packets to the remote
side even though they are broadcast packets. Before relaying a DHCP
message from a DHCP client, the agent examines the GIADDR (gateway IP
address) field. If the field has an IP address of 0.0.0.0, the agent fills
it with the router's IP address. When the DHCP server receives the
message, it examines the Relay IP Address field to see if it has a DHCP
scope (a pool of IP addresses) that can be used to supply an IP address
lease. If the DHCP server has multiple DHCP scopes, the address in the
Relay IP Address field identifies the DHCP scope from which to offer an IP
address lease. This process allows one DHCP server to manage different
scopes for subnets."

--

Thanks,
Marc Reynolds
Microsoft Technical Support

This posting is provided "AS IS" with no warranties, and confers no rights.


"Nathan" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) om...
> Marc thanks for the reply, article was good. but if one has only one
> DHCP server and multiple subnets, with out using a scope is there a
> way for the dhcp server to assign ip's? how would the dhcp server know
> which ip's to assign?
>
> thank you once again.

thank you both for your contrabutions, but i was asked this question
and did not have the answer so went looking for one. you two have
answered it for me.

thank you very much have a good one