Fritzbox 7590 as third party router on Sky Superfast Broadband

[SaschaNK]

Hi all,

I have read several threads about connecting thrid party routers to the sky network to replace the SR203 original router and all come down to using DHCPv4 Option 61 instead of PPPoE. Aparently Fritzbox does not support that. 

--> is this true for the 7590? 

Other people claim that most openreach connections (about 80%) in the UK are on native IPv6 anyway and don't need that

--> how can I find out if I am one of them or not?

And last but not least has anyone ever managed to set up a Fritzbox 7590 working in the sky network? 

[Chrisee]

@SaschaNK apparently it is the msnufacturer of the exchange kit that controls whether DHCP6 PD method works or it doesnt but there is no way of knowing in advance whether your line will work or not without trying it. 

[SaschaNK]

Thanks for the response! Is there a way to find out if thats the issue or just some of my settings being wrong? I can see in my fritzbox that it has a DSL connection but wont give me any internet access. I assume that is due to the (probably?) not supported DHCPv4 option 61 of my fritzbox. 

So I guess I have to try pure IPv6 for once and if that doesn't work it seems to be the case that the DHCP6 DP is not working in the exchange kit.

Are there any special settings for IPv6 I should be aware of?

[Chrisee]

@SaschaNK it could be your other settings so post pictures of the relevant pages and hope somebody sees the post and understands the Fritzbox. While Sky do support IP6  DHCPv6 PD is used to authenticate the connection which then runs a dual stack set up.

[-rpnz-]

Hi @SaschaNK 

Coincidentally I'm actually testing the FRITZ!Box 7590 for compatibility of a new feature now, so I have access to the interface and can share with you a screenshot of the IPv6 settings.  These settings should allow you to connect, if you are within the 70% of Openreach's footprint that supports Lightweight DHCPv6 Relay Agent (LDRA), that we require for authentication:

The `IPv4-Anbindung automatisch bestimmen` or `IPv4 Determine Connection Automatically" is to do with the new feature I'm testing, and you won't see that option yet. Future people reading this post  should enable this option if it's available.

[SaschaNK]

Hi @-rpnz- 

Thanks a lot for the settings and I guess I am quite lucy having you work on exactly that model. I seem to get connection but no internet. I have also no idea if the connection happens through IPv4 or IPv6

Here are some screenshots of my connected fritzbox

And these are the settings I used (the IPv6 page I set exactly like you had it)

I might have messed up something there from all the previous tests?

Regards

Sascha

[-rpnz- · Accepted solution]

Hi @SaschaNK 

On FTTC (both VDSL2 and G.Fast) services, we require VLAN tag with ID 101.

In your last screenshot, under "Account Information" -> "Connection Settings" -> "VLAN Settings", enable "Use VLAN for Internet access", and set VLAN-ID to 101.

Leave P-Bits empty or zero.

Assuming the IPv6 tab matches my screenshot, then that should do it; if not, then I'm afraid you might be in the unlucky ~30% without LDRA support.

[SaschaNK]

Hi @-rpnz- 

Thank you for that hint, that did the trick!

[josephgall87]

I have what appears to be a very unusual situation and no matter what I've tried I cannot get this resolved. I have a Fritzbox 7530 on Fritz OS 8.02. Using the settings above, my Fritzbox connects perfectly to Sky FTTP. However, after exactly 30 minutes (and every 30 minutes thereafter) the Fritzbox momentarily loses connection, the box appears to be renewing it's WAN IP address (the IPv4 doesn't change but the IPv6 does). I have read on other forums that this could be the box trying to renew the lease on the WAN IP address but the connection definitely drops for a few seconds each time it does. Any suggestions on how to overcome this? I have a TP Link AX55 router that does not do this while connected to the same line and ONT.

[josephgall87]

@-rpnz- if you are able to assist, I would greatly appreciate. Thank you.

[-rpnz-]

---

@josephgall87 wrote:

I have what appears to be a very unusual situation and no matter what I've tried I cannot get this resolved. I have a Fritzbox 7530 on Fritz OS 8.02. Using the settings above, my Fritzbox connects perfectly to Sky FTTP. However, after exactly 30 minutes (and every 30 minutes thereafter) the Fritzbox momentarily loses connection, the box appears to be renewing it's WAN IP address (the IPv4 doesn't change but the IPv6 does). I have read on other forums that this could be the box trying to renew the lease on the WAN IP address but the connection definitely drops for a few seconds each time it does. Any suggestions on how to overcome this? I have a TP Link AX55 router that does not do this while connected to the same line and ONT.

---

Hi @josephgall87 

I too have a FRITZ!Box and noticed it resets its connection time counter everytime it renews the DHCP leases, but for me this doesn't cause an outage, or the IPv6 prefix to change, it's purely cosmetic.  In saying that, I'm still on 8.00, haven't upgraded to 8.02 yet.

The usual causes for an IPv6 prefix changing are:

• Client sends a DHCPv6 Release message (some routers send this during a reboot)
• Client changes its DHCPv6 Unique Identifier
• Client changes its MAC address

I don't believe the FRITZ!Box is doing any of these, and there aren't any configuration settings to adjust them anyway, so I'm not too sure to be honest.   

In the WAN settings, have you selected "Connected to a fiber option modem (ONT)" or "Connected to an external modem or router"?

In the WAN IPv6 settings, have you ticked "Automatically determine IPv4 Connectivity", to request MAP-T, or unticked for dual-stack?   Try the opposite of what you have currently set here and see if that helps.

Also in the WAN IPv6 settings, under "Connection Settings", which option have you ticked there?  Sky doesn't provide a dedicated WAN address, so you should tick "Derive global address using the assigned prefix" option.

And untick "Use DHCPv6 Rapid Commit".

Admittedly those are just me clutching at straws, but if you confirm those and still have issues, I'll upgrade my F!Box to 8.02 and if I start having issues, then we know it's a new bug.

[josephgall87]

@-rpnz- thanks so much for replying so quickly. Really appreciate it.

In answer to your questions, I have selected "Connected to a fiber option modem (ONT)" in WAN settings, I have ticked "Automatically determine IPv4 Connectivity" (unticking does not resolve the issue),  and I have tried ""Derive global address using the assigned prefix" and also "Automatically negoiate a global address" and both allow me to establish a connection but the 30 minute disconnect/reconnect happens on both. Also "Use DHCPv6 Rapid Commit" is unticked. From a browsing point of view it isn't really noticable however when on a VOIP call through the Fritzbox, it drops at that very moment of the lease being renewed every 30 minutes, I have tested this about 7/8 times and it does it every single time. One other thing to mention, I tried changing the DNS and experimenting with DoT DNS on and off and I have the same outcome.

[-rpnz-]

And the IPv6 prefix definitely changes?

It's possible the issue isn't as aesthetic as I initially thought, perhaps they re-apply the firewall rules each time, which would cause existing flows to stop and have to re-establish. (I haven't thoroughly investigated it to be honest).

I'll upgrade my F!Box and see if I start noticing connectivity issues.

[josephgall87]

Thanks @-rpnz- Sorry I have checked again and no the IPv6 prefix does not change, so neither the IPv4 address changes or the IPv6 but the connection drops. It's so strange, it is so momentary that it might be missed unless you are using something in real time like VOIP or maybe gaming I would presume? But it is definitely happening, I am presuming if it is an issue, that it will be with the Fritz OS rather than with Sky?

[josephgall87]

Hi @-rpnz- just wondering did you ever get a chance to test this yourself? Thanks!