Question

Guys

Looking to use a RUT device to provide a 4G WAN off the back of a UTM device.

Is there any best practice document or use case here for the configuration?

I am assuming the RUT can be configured as a modem, with the UTM controlling the session?

If one LAN port is setup as a modem connected to the UTM, can another LAN port on the RUT be used to access (browser or telnet) the device for stats or config? This is an issue I have fought on other 4G router devices and not found a sensible solution.

Thanks in advance for any wisdom.

David

Answer 1

Hi,

 

RUT device is good choice to use as 4G WAN gateway. For example, RUT240, RUT950 supports three mobile connection operating modes:

• NAT - the mobile connection uses NAT (network address translation).
• Bridge - bridges the LTE data connection with LAN. In this mode the router relay the IP address received from the ISP to another LAN device (e.g., computer). Using Bridge mode will disable most of the router’s capabilities.
• Passthrough - works in a similar fashion to Bridge mode, except in Passthrough mode the router will have an Internet connection and be reachable from LAN, because the router's DHCP Server is not disabled

If you set Passthrough mode, public ISP IP address will be relay to UTM. But at that time DHCP server of RUT is enabled and local devices can be connected to LAN ports. They can access router and have internet connection.

More info you can find on Teltonika wiki:

https://wiki.teltonika-networks.com/view/Mobile#Passthrough_mode

Comments

Hi

Thanks for the reply. However I am struggling to get this working.

The RUT240 connects to the mobile service with no apparent error. Firmware is RUT2XX_R_00.01.12

I have the RUT240 WAN port set as LAN, and is connected to the internal LAN, so I can use that port to manage the RUT240 from a browser on a PC.

The LAN port on the RUT240, connected directly (straight cable, showing link up) to the UTM on a spare interface, which is  defined as a WAN (ie external).

I have the RUT240 set in Bridge mode, and I have set the correct UTM interface MAC address set in the RUT240

Question:

What should the UTM WAN interface be set to: PPPoE or just DHCP? From what I have read, its DHCP only, however the "Mobile Configuration" page has an option for "Connection Type" PPP - is that between the RUt240 and the carrier?

If I set the UTM interface to DHCP,  so assumed that it would pass, using DHCP, the 4G IP address to the UTM, but the WAN on the UTM picks up a LAN derived DHCP assigned IP address which it has acquired via the WAN interface on the RUT240 which is of course connected to the local LAN to manage it.

If I set the UTM to PPPoE, the link is up (no surprise there) but no IP address is assigned on the UTM interface.

SO - problem is that the UTM is not getting the mobile network provided IP address via DHCP provided by the RUT240.

The RUT240 system log shows "Found already running DHCP-server with X.X.X.X gateway - does this cause the RUT240 DHCP service to stop, hence it appears the Mobile assigned IP is not being assigned to the UTM.

If I remove the LAN connection from the RUT240, and leave it connected to the UTM, then the Carrier IP address IS assigned to the UTM using DHCP - GREAT! - but how can I manage the RUT240 without that LAN connected? I dont want to accept remote management for the RUT240 across the WAN.

Thoughts?

David

Answer 2

Hello David,

Q: What should the UTM WAN interface be set to: PPPoE or just DHCP? From what I have read, its DHCP only, however the "Mobile Configuration" page has an option for "Connection Type" PPP - is that between the RUt240 and the carrier?

A: Yes, connection type PPP is between the RUT240 and the carrier.

Q: If I remove the LAN connection from the RUT240, and leave it connected to the UTM, then the Carrier IP address IS assigned to the UTM using DHCP - GREAT! - but how can I manage the RUT240 without that LAN connected? I dont want to accept remote management for the RUT240 across the WAN.

A: Use Passthrough mode instead of Bridge. In Passthrough mode the router will have an Internet connection and be reachable from LAN, because the router's DHCP Server is not disabled. After changing modes, additionally check “Use WAN port as LAN” it could be disabled. So you have to set it again.

First of all, I think you should temporally disconnect UTM and use only PC. Connect it to RUT240 LAN port (not WAN as LAN). Set your PC’s MAC address on Passthrough tab (Network → WAN → Mobile Configuration). Does your computer have an Internet connection? What IP address did he get?