TRB500 limitations of bridge mode - and what to do

[LHH]

I suppose that I need to get more information on

• the difference of bridge and passthrough modes
• the implications and advice on what is most suitable to me
• hear how to solve some needs

Lets start at the top and I’ll provide info as we progress.

The difference of bridge and passthrough modes
If there is any link to a good explanation that would be awesome.

When on the admin page /network/wan and setting the mode for WAN the description below is given

Using Bridge or Passthrough mode will disable most of the device capabilities and you can access your device’s settings only through its static IP address!

Mobile Bridge mode troubleshooting - Teltonika Networks Wiki gives some more information but it’s not super clear.

using Bridge mode will disable most of the router’s other capabilities (NAT, Firewall, DHCP server…) and router will not have internet, will not be accessible through the RMS platform

The implications and advice on what is most suitable to me
My current setup is with the TRB500 in bridge mode and used as WAN connection for a Ubiquiti UDM-SE.

Some needs/limitations I’ve noticed and would like to either overcome or get explained.

• the package manager at /system/packages/packages show no packages available, nor installed
  
  
  
  
• now and then the TRB500 get the wrong time set despite having NTP enabled at /system/admin/datetime/ntp
  
  

hear how to solve some needs

• What is the difference between bridge and passthrough mode?
• In which cases are each applicable and which are their strengths and weaknesses?
• Are the package manager and NTP issues a drawback of bridge mode and how can each be solved?
• When should NAT-mode be considered and would it lead to other downsides - which?
• Which would you use when having the TRM500 as WAN provider for a Ubiquiti UDM-SE, or similar network equipment?
• Did I miss any info that would be of importance for you to help?

Device info

   Device:     TRB500
   Kernel:     4.14.319
   Firmware:   TRB5_R_00.07.05.4
   Build:      d48a3687a6
   Build date: 2023-11-07 15:10:16

[clive.simon]

Hello,
Welcome to Teltonika Networks Community !
Kindly refer to the below posts for a better understanding of Bridge and Passthrough modes.

Differences with Mobile Modes (NAT, Bridge, Passthrough)

Hello, I’ll go over each of the modes and explain a little about all of them: NAT mode This is the most commonly used mode - it handles L3 routing, as well as NAT (Network Address Translation). In this mode, managed Teltonika products can support more than one LAN client, by providing each of them with a private IP address. If you have a public IP address on your mobile interface, port forwarding can be configured to forward specific ports to LAN clients. Some people also treat NAT as anoth…

The main difference between Passthrough and Bridge is that in Passthrough, the router’s DHCP Server still works and the regular LAN interface is still up, allowing clients to connect to the router’s local network as usual and the connected devices will have WAN access too, while Bridge mode disables all of these features and simply gives the a single specified device its WAN IP address, but if DHCP is enabled the devices connected will only have local access.

The issues you are facing can be resolved by using passthrough mode instead.

Moving further on passthrough mode is used when you still need a local network and connectivity to our router - Like in the case of Helium Miners Providing connectivity for Helium miners using the RUT240 - Teltonika Networks Wiki

Also an important point, i would advise you to retest using the latest FW TRB500_R_00.07.06.1 , as it comes with a patch that greately enhances Passthrough and Bridge modes.

Regards,
Clive Pinto

[LHH]

Thanks for you reply. I’ll digest the information you liked to.
The following section cause some confusion.

@clive.simon

The main difference between Passthrough and Bridge is that in Passthrough, the router’s DHCP Server still works and the regular LAN interface is still up, allowing clients to connect to the router’s local network as usual, while Bridge mode disables all of these features and simply gives the a single specified device its WAN IP address.

My current setup is with the TRB500 in bridge mode and used as WAN connection for a Ubiquiti UDM-SE.
The experience in bridge mode in my set up seem to match what you describe about passthrough.

1. My UDM-SE get the IP address of the TRB500
2. The TRB500 is reachable from the internal network using 192.168.0.1

Is it that for TRB500 there is no difference between bridge or passthrough?

[LHH]

Further, in the linked reply the following statement is given bu the same author

WebUI is only accessible when using NAT mode.

This seems to be incorrect information for TRB500 in bridge mode, where I indeed have access to log in to the device from my LAN using 192.168.0.1.

[clive.simon]

Apologies, it was incorrect, i have revised it.
Basically - In Passthrough and Bridge DHCP works, but in passthrough the connected LAN devices will have WAN Access, while in Bridge mode its just internally the devices will be connected to each other only and one device will have exclusive WAN Access.

[clive.simon]

Correct, it was later agreed in the later comments. The WebUI can be accessed in Bridge mode if the existing routes are present or a static IP or route is set.