DHCP Reservations

[Dave Rees]

Hi,

We have a win 2k server running DHCP serving 15 subnets
which are in a superscope.
This is working fine except that we have some laptops
that connect to a piece of software that requires them to
have a fixed IP address.
The default lease period (8 days) works fine.

Now the problem is that if the laptop moves to a
different site (different subnet)then the software won't
work. If I add a reservation in then I can give it a
fixed ip address everytime but if I add a second
reservation in it always gives out the first reservation
it finds regardless of whether it's in the correct subnet
or not.

I.E.
Subnet 1
172.16.0.0/24
No reservation

Sunbet 2
172.16.2.0/24
Reservation 172.16.2.201 Picks up this address

Subnet 3
172.16.4.0/24
Reservation 172.16.4.201 Even if I am at this site

If I remove the reservations it will pick up a correct
subnet address without a problem.

Should the DHCP server be checking whether the request is
coming from the subnet with the reservation or is it just
checking the MAC address and giving out an address based
on that?

Any ideas how I can get around this?

Thanks

Dave Rees MCP

 

[Phillip Windell]

That is not what Superscopes are for. Get rid of the Superscope!

Use individual Scopes for each subnet. No Superscopes!

See how it behaves after this. If it still has problems, then at least you
have a properly design system to work from.