Cable network - Unitymedia

I have Unitymedia in germany as provider with 150Mb/s. Because Deutsche Telekom terminatet my ISDN contract for telephony I had to change to Unitymedia for telephony. They sent me an ‘Fritzbox Cable 6490’ to replace the Cisco modem. Everything works fine so far.
But: My Turris Omnia has now (via DHCP) an IP Adress from my home network ( As this is a private IP aqdress, it cannot be reached from the outside network. Does this has any influence to the Turris Omnia features (e.g. updates)?

updates: no
also no routing stuff should be affected as long as the ip on the wan side is not in the same subnet as your lan.

but other stuff like honeypot or dynamic firewall will be even more useless…

you can/could go to cable provider customer service (portal) and turn the modem into bridge mode. that would give your omnia the internet-ip.
but then telephony function of the modem would probably not work and given that you just recently migrated from isdn, i take it you really really like your pots-equipment and dont want to know anything about voip-phones :wink:

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Unitymedia doesn‘t allow bridge-mode, just google it, there are many stories of people whi tried (and failed).

If you want your network to be reachable from the outside you could use ipv6 (unitymedia-„modems“ support ipv6 prefix-delegation) or you could rent a vserver with an public ipv4 adress and use OpenVPN and source-nat to forward request from the internet to services you provide. Or take a look at

Be aware that this is only for advanced users.

If you just want to use your Omnia as a „normal“ SoHo-Router everthing will work just fine.

The following is only if you want to use more advanced features like having a server reachable from the internet. For normal use cases your current setup should be fine.

It is possible to define the TO as an “Exposed Host”. This will relay all traffic that comes from the internet to the TO. On a german Fritz.Box interface it would be at Internet>Freigaben>Geräte für Freigaben hinzufügen there choose the TO in the dropdown and check all the checkboxes on that page.
After that you can also have servers and stuff behind the omnia that will be reachable over the internet (ipv4 connections).

Depending on the version of the you can also get the TO manage an ipv6 subnet for your local network (from my experience this only works correctly from Fritz!OS version 06.87 onwards):
At Heimnetz>Netzwerkeinstellungen>IPv6-Adressen select the options “DHCPv6-Server in der FRITZ!Box für das Heimnetz aktivieren:” and “DNS-Server, Präfix (IA_PD) und IPv6-Adresse (IA_NA) zuweisen”

Hi Skywalker-11,
how to get Fritz!OS version 06.87 from Unitymedia? I still have 6.50. I am using the exposed host from beginning to be able to reach home over IPv4. As Sixxs has ended with IPv6 tunnel, I am so far without IPv6, but I would like to have it parallel to IPv4 from Unitymedia. I don’t want to loose IPv4 by switching to this crazy DS-Lite and your post looks like I can get it. Do you have also English names for this options as my Fritzbox is in English? Thank you
Best Regards

To be able to use IPv6 you must already have an IPv6 prefix supplied by Unitymedia. I don’t know exactly if you can get public v4 and v6 from Unitymedia.
For english gui the IPv6 settings are at Home Network>Home Network Overview>Network Settings>IPv6 Addresses. The settings to check are “Enable DHCPv6 server in the FRITZ!Box for the home network:” and “Assign DNS server, prefix (IA_PD) and IPv6 address (IA_NA)”

I’m using a business access from KabelDeutschland where I get both public ipv4 and ipv6 and the mentioned Fritz!Box firmware version. So it could also be that Unitymedia is blocking on of the mentioned settings

Problem is solved:
Unitymedia has 2 types of customers: Private and business. I changed my plan from private to business and got 200/20 Mbit instead of 150/10 Mbit. (for the same price!!!) On top I got a fixed IP4 IP adress.
The Fritzbox from Unitymedia gets it’s IP via DHCP, my Turris Omnia has now a fixed IP. So there is now no restriction for updates.
AND: The business support people are much better knowledgeable and could help me immediately. They knew the problem as many business customers use their own routers.
Many thanks for your help

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I was playing with it whole weekend and I got stuck little bit before end. What I did:

  1. I have configured IPv6 on Fritzbox by using 6in4 from, so I have added ipv4 server and both IPv6 addresses of the tunnel. I have also added the assigned prefix /48

  2. I have changed on Fritzbox the DHCPv6 server to assign also IA_PD

  3. On Turris I have modified WAN6 and changed it to DHCPv6 protocol
    Result -> all devices get IPv6 address and they are able to communicate outside. The IPv6 of TO is xxxx:0:yyyy where xxxx is /48 and yyyy is address of the device, all devices in LAN get IPv6 in range xxxx:80:yyyy where 80 is the automatic choosen subnet.

  4. I have added in Fritzbox yyyy to Permit access on IPv6 tab as Interface ID to allow inbound communication.
    And here come the problem -> Fritzbox allow me only to communicate to subnet 0, not to subnet 80. When I try to ping address with subnet 80, I receive error: Destination unreachable: Administratively prohibited

Any idea how to change the setup, that the inbound communication to LAN part of TO works in this setup is welcome.

Can you ping the TOs IPv6 from a device directly connected on the FB (fe80:…:yyyy or xxxx:80:yyyy)?
If also the fe80 address is not pingable make sure that the TO firewall allow icmp-ipv6 echo. If the fe80 address is working but the xxxx:80:yyyy is not it is probably a problem with routing. You can try manually adding a static ipv6 route for the xxxx:80/z to the fe80:…:yyyy address of the TO on the FB.
After that at least devices directly connected to the FB should be able to reach the TO.

You can also try running ifstatus wan6 on TO. It should display the assigned/routed ipv6 prefixes for the TO.

Also make sure that you have the TO set to exposed host that allows delegated prefixes if it should be reachable on the Internet.