Question

Dear Team,
I have some problems to configure a TRB140.

What I need:
Modem in 'Bridge' mode, the provider supplies a fix IP and Gateway and two DNS, the router connected to the WAN-port by cable use the modem.

What I get:
Connection is up. For about 10 seconds I can access the internet from within my network, ping & open Web sites, than the traffic is interrupted for some reason and after ~30 seconds the router reconnects, and the cycle starts over.

What do I found out:
On the WAN port of the TRB140 there is also the privat traffic (192.168.2.1 modems default) available.

My guess:
This packets disturbing the router and so the router shuts down the connection. After 30 seconds the router performs a reconnect.

Is there any chance to separate the internet traffic (between the modem and t-mobile infrastructure, LTE connection) and the privat traffic between lets say a laptop and the modem ( WebUI of the modem) using the USB cable only.

With my old Netgear FVS336G the modem works fine. When I connect the modem to this router I first get addresses from the 192.168.2.x net, but when I reboot the router after I connected the modem the WAN port of the router gets all the addresses from my internet provider and connection is stable.

Thanks a lot for helping.

With best regards

Gerhard

Answer 1

Hi,

Please can you clarify if your topology is as depicted below ?  Note : Once the "bridge mode" on the TRB is invoked it assigns the WAN IP address to another device (first connected to LAN or specified with MAC address). Using Bridge mode will disable most of the device’s capabilities including the DHCP. Therefore either an intermediate device is leasing out the 192.168 or you may have set the mode to "pass through" on TRB ?

TRB140    >>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Wan port of ROUTER >>>>>>>>>>>>>> PC on router LAN port ?

(Bridge mode)

Thanks

Comments

Hi,

I confirm this topology.

But there is little bit more involved:

TRB 140 (WAN) >>>>>>>>>cable>>>>>>>>>>(WAN) Router (LAN) >>>>>>>>>>>> (cable & switches) Local network

               (USB) >>>>>>>>> USB cable >>>>>( driver) Laptop

I only need a modem, so I set the TRB 140 in bridge mode.

You wrote about the DHCP functionality and that this functionallity isn't supported in bridge mode, but: When I disable the DHCP nothing works.

My actual problem is the 'bridging ports' thing at the TRB 140. It looks to me, that the TRB 140 internally connects its USB 'network' port and its 'WAN' port, so the WebGUI can be reached via both interfaces. My guess is, that the Lancom-router doesn't want things like that.

Here what I get with 'bridge mode', this is reported by Lancoms 1790 EF router:

There is only a simple cable between TRB 140 WAN connection and 1790 EF WAN connection. TRB 140 in bridge mode and I get an address of the DHCP on TRB 140, which has its factory set network 192.168.2.x

This is correct assignment and with that the TRB 140 and 1790 EF connection to the internet for about 10 seconds. Ping: ok, Browsing: ok. After 10 secondes the traffic stops to no reason and after 30 seconds more the router disconnect. And reconnect immediately. There is no issue with RF receiption (I am a HAM radio operator, I can say this clearly).

This is my motivation to do whatever is needed to get a clean network traffic over the WAN port of the TRB 140 and nothing else.

Maybe you can send me a configuration file for the TRB 140 working as a clean bridge.

With best regards

Gerhard