DHCP not working properly

[Kenneth Mohammed]

I have 5 C9300L-48T-4X-M switches. I currently have them daisy-chained together (stacking cables havent arrived yet).

We are pre-staging these switches in a shop environment before shipping to the customer.

The switches register with the dashboard fine, as they receive a management IP from the shop VLAN via DHCP.

I set up the core switch as a DHCP server for 2 VLANs, and configured the downstream switches with the corresponding port VLAN configurations etc.

The problem is, clients in either of these VLANs keep getting link local IP addresses, or addresses from the shop DHCP server, which i want to prevent.

Why isnt DHCP working? This is all so very simple to setup on a regular cisco switch.

[Ryan_Miles]

@Kenneth Mohammed Are the VLANs trunked all the way down to these switches? Or, are the client VLANs local to the C9300s and you have a DHCP relay configured to forward the requests? A diagram or some pics of the config would be helpful.

Cheers

[Kenneth Mohammed]

Yes, the uplink ports are all set as trunks, and allowing all VLANS. The client VLANs are local to the C9300s. The layout is as follows:

<shop network> ------ SW1 (DHCP server) ---(trunk)---SW2 -----(trunk)------SW3---(trunk)---SW4---(trunk)---SW5

[joey.debra]

If your clients get DHCP from the shop VLAN that means those clients are in the wrong VLAN and just get DHCP from the upstream shop VLAN.
Your two VLANs that are terminated on your core switch should not be serviced by the shop DHCP server. So you should check on which VLAN the MAC address of the client is coming from. I'm pretty sure you have a VLAN hop issue in your network due to a native VLAN mismatch or just blending both shop and client VLANs together.

You can also use dashboard captures with filter 'port 67 or port 68' to see all the DHCP messages passing to a certain port on the switches.