GL-MT3000 not working when connecting WAN to HG8040H6 modem

Routers
1

I tried connecting my GL-MT3000 to my China Mobile modem (Huawei HG8040H6) LAN port #4 but the DHCP setup doesn't complete. I have another TP-LINK wifi router connected to LAN port #1 and it works fine (I believe it also uses DHCP to get an IP from the modem).

I checked the HG8040H6's admin page (http://192.168.100.1/) and don't see any MAC address filtering or some kind of whitelist that would prevent the MT-3000 from getting an IP. The DHCP server is enabled and settings seem configured correctly (see below). The MT-3000 is listed in the device list but doesn't have an IPv4 address listed.

LAN configuration of Huawei modem:

Primary IP Address: 192.168.100.1
Primary address subnet mask: 255.255.255.0

DHCP configuration of Huawei modem:

Enable the primary DHCP server: :white_check_mark:
Enable DHCP relay: :white_check_mark:
Enabling Option 125: :white_check_mark:
LAN host IP address: 192.168.100.1
Subnet Mask: 255.255.255.0
Starting IP address: 192.168.100.2
End IP Address: 192.168.100.254
Lease period:1 day

Not sure what to do. I tried connecting the MT-3000 via ethernet to my TP-Link router instead and everything works fine. I would rather connect directly to the modem though to avoid an unnecessary hop.

GL-MT3000 - Yellow “Connecting…” status
2

What IP address does your tp-link router get from your modem?

BTW, the modem seems like a normal router. Generally modem passthrough public IP to the router connected.

You can also try:

  1. Reboot the modem
  2. Disconnect the TP-Link and clone its mac address to the MT3000
3

It doesn't seem to passthrough the public IP. The IP assigned to the TP Link router is 192.168.1.1. I tried rebooting the modem as well.

4

This is the IP of TP-Link's LAN. We need to see the WAN IP.