DHCP from Service Provider Not Working

[mtnchaser]

Good Day,

Fighting an issue with DHCP from the service provider. Just not getting it.

So I have  a 2600 that I have configured three sub interfaces on. FA0.0.1 is set for DHCP and supports VLAN 1. FA 0/0.2 for Voice, FA 0/0.3 for Data.

I have this router interface plugged into FA 0/24 on my 3550 and the 3550 is configured as a dot1Q trunk (I have attached configs for RTR and SW).

I have most ports configured as access VLAN 1 which is where i have my ISP connection plugged FA0/1 on the 3550.

When I connect the service provider link FA0/0.1 never picks up an address. If I take my internal DHCP server and connect it to FA0/1 of the 3550 it snags an address almost immediately.

In my mind this validates that my config is fine. I also took the same cable from the service provider cable modem and connected it to my laptop and the laptop is pulling DHCP.

Been pulling my hair out on this for a few hours now. Any advice? Am I missing something really stupid?

Thanks in advance.

Joel

[paul driver]

Hello Joel,

This is possibly due to the ISP having registered the laptop mac address, try spoofing your router wan interface with the laptops mac.

int (wan interface)
mac  xxxx.xxxx.xxxx

res

Paul

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