Tunnel lan port 2002 (from specific host) to wan device

I have a tvbox from my provider which normally is directly connected to one of the lan ports of the cable modem from the provider.

As I have them in different rooms and the connection has to go over 2 switches and my own router the box cannot connect to the cable modem. The provider told me that the box needs to be able to access Port 2002 in the WAN connected cable modem.

So, how do I make sure that port 2002 from an internal mac/ip will be tunnelled to the WAN device cause I think normally packages from internal ip’s are blocked by various methods. firewall rules, bcp38, etc.

Does anyone have instructions on how to set thisi up? Would be really great

Is your Cable Modem running in bridge or router mode? Either way it is very likely that what you try to archive works by default. Your cable modem is accessible through the WAN interface and every traffic from LAN to it is masqueraded (NAT) like any other connection from LAN to WAN.

Well as you might have read - the tvbox does not work (mostly). This means that it always complains about “service locked” and wants me to setup the Networking Connection. And no matter if I choose Ethernet or WLAN it the always says when it tries to connect “wrong network” which according to the cable company means the tvbox could not connect to the cable modem and therefore thinks I’m not connected to the cable companys network.

Strangely enough if I try 4-6 times to establish a network connection sooner or later it works. But if I switch off the tvbox and restart it the problem is back.

I already tried setting a static entry for the box with predefined ipv4 & ipv6 settings but it does not help. It always takes me numerous attempts to get a working connection from the tvbox passing the 2 switches and the TO to reach the cable modem. So the connection is:

tvbox → switch 1 (home entertainment cupboard) → switch 2 (house media distributor) → TO → cable modem.

I don’t where to tweak to make it work and the cable company is also not helpful at all as they say only direct connection from tvbox to cable modem is supported. It’s just not possible in our case. The only hint I got was that the tvbox wants to connect to the cable modem on Port 2002. But if as you say this is anyhow possible why does the box most of the time say it cannot connect and does not display any channel, recordings or other content?

So TO‘s firewall can‘t be the problem as it would either work or not if this would be the problem…

It sounds like a discovery problem… I don’t know your tv box so I can only guess it could use ICMP, avahi or some vendor specific protocol to discover your cable modem. So you could need some kind of ICMP or avahi proxy service running on your TO, which is possible to set up (although out of my knowledge).

I know that some TV boxes only work stable if IGMP snooping is enabled (LuCI → Network → Interfaces → LAN-Interface → Physical settings → enable IGMP snooping).

Which TOs version are you using? There are some connection issues with TOS 5.X on its internal switch, you could try to switch your Ports so that your cable modem is connected to LAN4 Port and your switch is connected to the WAN Port of your TO. See this post for instructions: Turris OS 3.11.23 -> OS 5 - recommended to wait due to issues? - #4 by protree - SW help - Turris forum

Again, is your cable modem running in modem (bridge) mode or router mode? If it runs in router mode you could bridge its network to your tv box through a vlan but this would require managed switches.

These are just some ideas, but maybe one of them will point you into the right direction :slight_smile:

I’m indeed running TOS 5.x and I think the problems started after I moved from 3.11.23 to TOS 5.1.x, will try to follow that instructions.

Sorry that I forget to mention, the modem is running in bridge mode so fully transparent.