So just to explain a bit further. VR2100v MUST only be "modem" in this case. There is real router behind VR2100v. VR2100v must use IP of the real router to gain internet access. That seems impossible since under "Network > Internet" options on VR2100v you can't set that it uses LAN1 port for internet access for example.

  @David-TP

 

It is already like this case on the link you sent.. I've already did that.

 

But when you do that, then VR2100v doesn't have access to internet because he doesn't know that (in this example Archer C7) is the main router. VR2100v needs a "default route" to Archer C7 in order to go online, and there is no way to input that.

 

You can set a static routes to use gateway (Archer C7 in this example) for a specific subnet, but not to all subnets (therefore the default gateway option - if static routes are used, it should be 0.0.0.0/0 and gateway should be IP of the Archer C7).

 

For example, I can't check for new firmware on VR2100 in this case, because it is not connected to the internet and doesn't knows how to connect because it has no gateway.

  @David-TP  It's not what I want.

See here under Advanced Settings, you go to Network > Static routing. There is a selection for Default gateway but you can only select your VDSL connections and you can't select LAN as a default gateway.

 

 

It should have LAN to select here so the router itself connects to the INTERNET using the LAN port, instead of VDSL. VDSL is used for VOIP, IPTV and acts as a bridge between VDSL and another router.

 

It can't connect through VDSL VLAN's when these WAN interfaces there are used for VOIP and ACS/CWMP.

 

I've added as you can see a static route to the rest of my network, but I can't set 0.0.0.0/0 as destination (would be same as default gateway).

 

Edit to clarify a bit more:
 

 

So as you can see, the router's WAN interfaces do not have access to the Internet. But the Ethernet LAN UTP cable connected to the LAN port on the router HAS Internet access.

 

The router needs to connect to the internet through that port, and that's not possible to select.

Another thing: If you select under "Operation mode" > "Wireless Router mode", then you can set ipoe_0_s connection and enter a default gateway, but then you can't use the modem for bridging VDSL to the main router.

 

If SSH worked it would be literally one command:

 

# route add default gw 192.168.88.254 eth0

 

And the VDSL modem would have a gateway and show connected to Internet over LAN port.