SXT-LTE bridged mode?

RouterOS General
21

Bump on this old thread.
I just got a SXT LTE 6 thinking to set it up as a drop-in replacement for a NetGear LB1111 that I use in ‘bridge’ mode to connect to a dual router Zyxel LRT224.
The Netgear is ‘transparent’, gets the public IP from the LTE provider, and passes it to the Zyxel, or to any single PC attached to its port.

For the sake of me I cannot find a way to setup the LTE6 to do the same: firmware RouterOS 6.47,disabled NAT and DHCP, bridged WAN with ethernet 1, no luck.
It seems like such a basic feature, I can’t believe the LTE6 is not capable of that!
In the Netgear LB1111 you have two modes, ‘router’ and ‘bridge’, switch between the two and you go from a router to a pass-through modem.
I did also the same realtively easy with a TIM - provided ADSL modem, and with an Asus N55U ADSL modem, same thing, switch from rotuer to ‘bridge’ and connected also to a WAN of my LRT224

I also contacted Microtik technical support, has anybody made this to work in 2020?

22

nicobar :



  1. You should create a new post
  2. You not read documentation who describe that feature: https://wiki.mikrotik.com/wiki/Manual:Interface/LTE#Passthrough_Example
23

This is an old thread but it's the first one if you type sxt lte bridge or passthrough into Google. Mikrotik did add this feature and it works very well.

Edit: I missed that someone had answered this. The link above is dead, new link here:
https://wiki.mikrotik.com/Manual:Interface/LTE#Passthrough_Example

The best way I've found to use it is this

  • connect from win box using Mac address
  • clear all config
  • create bridge
  • add eth1 and eth2 to the bridge
  • add a DHCP client on the bridge so the sxt gets an IP (for management)
  • add a VLan to the bridge, say VLAN99
  • go to APN settings, enable pass through and select VLAN99, configure other apn settings
  • on the second router, add VLAN99 on your bridge
  • add a DHCP client on VLAN99
  • setup VLAN99 to be your wan

This setup has the advantages

  • you can manage the SXT as normal
  • you can plug into either port on the sxt
  • you can use the other sxt port as part of your lan
  • VLans will work between your router and spare sxt port
  • the sxt can receive updates
  • the sxt is portable between routers because it's using DHCP client.
  • sxt config is the absolute minimum
  • you can add a switch between the 2 devices without having to configure the switch (assuming it passes VLans). This could be useful if a PoE switch is being used to power the SXT.
  • you can basically plug the sxt into any lan port on the router

Make sure the VLan is a slave of the bridge NOT on the bridge itself.