ip-helper with two subnets

[s.hellman]

We have a 4908 where we have two subnets on the first physical port, 10.5.1.0 and 10.5.1.11, and the IP-helper points to the DHCP-server. If a computer on this first port broadcasts for an IP it will get one in the 1.5.1.0 span, but how could we configure it if we want that some computers should have ip-addresses in the 10.5.1.0-span and the some in the 10.5.1.11-span? The relay agent always forwads it as a 10.5.1.0 broadcast.

[glen.grant]

Are you using a secondary address seeing that you have 2 subnets on one port . If so it is always going to use the primary address as the broadcast and there is really no way around this

that I know of short of putting the subnets on different ports . I don't believe dhcp will work on a secondary address.

[s.hellman]

Yes, 10.5.1.0 is the primary and 10.5.11.0 is the secondary.