I have a Netgear 48-port managed switch and a Linksys 24-port unmanaged switch. I have connected the Netgear to the Linksys via the uplink port. Systems connected to the Linksys are not getting an IP address from our DHCP server, but when the same systems are connected to Netgear it works fine. Why?
The Linksys switch, being an unmanaged switch, cannot understand where to send BootP/DHCP requests; hence this issue. Move the Linksys switch off of the uplink port to any of the other Layer 2 ports. This will make Linksys an extension of Netgear. If you are using a fiber connection, try changing this to a cross-cable connection.
Another approach to try, though a long shot, is to define an "IP helper-address" on Linksys as the management IP of the Netgear switch.