Switching to Sky Broadband FTTP from Virgin, router config questions

[ChrisGreen]

Hello
On Thursday I'm finally leaving Virgin (which I currently use for broadband and landline phone) and moving both services back to Sky. I already have Sky Q and several min boxes, and was previously a Sky Broadband DSL customer in the past. However, the pandemic shift to working from home necessitated more bandwidth than I could get over DSL at the time so had to switch to Virgin. No longer an issue as Openreach full fibred the street last year, so can now get FTTP.

Anyway, I have some questions about trying to replicate/retain my existing home network setup. I currently run my Virgin router in modem mode, and that is connected to a three-node TP-Link Deco mesh network, with the primary Deco node acting as router. I have a Pihole handling DNS.

I know that Sky routers do not have a modem mode, and I suspect I will not be able to discard the Sky router entirely in favour of directly connecting the Deco to the ONT as 1) I need to retain a VOIP landline and 2) I don't know if the Deco would support direct connection to the ONT anyway.

Last time I was with Sky Broadband I used a guide (think it was from the now defunct SkyUser forums) to configure the router Sky supplied back then in such as way that it minimised the impact of double NAT, setting up a DMZ and disabling DHCP etc. and effectively operated as a WAN connected to my own router that then did all the heavy lifting.

However, while that setup worked, it was also before I had migrated to Sky Q (still had my Sky+ HD box, which was more forgiving of such things). So, what I am hoping you can all help advise me on please is this:

1) I want to keep the Deco Mesh and don't want to just use it as an AP network (I would rather it continued to handle all router functions). What are the setting changes I need to make to the Sky router to replicate what I had before please and minimise the impact of double NAT etc.?

2) How do I make sure the Sky Q and mini boxes play nicely with this setup (all bar one are wireless in the house, one is ethernet connected as it's next to the router)? They all work fairly well at the moment (the Wi-Fi mini boxes occasionally fall off the Deco network, but not often. Can't remember the last time the primary Q lost its wireless connection) with my existing Deco mesh network setup and Virgin connection. Anything I need to change?

I've seen instances where people using third-party Wi-Fi networking hardware alongside their Sky router (with Wifi disabled on the Sky router) resulted in the Q boxes constantly falling off the wireless network. Ethernet is not an option for the ones currently wireless.

3) Any other advice or config suggestions I need to be aware of please?

Thanks

Chris

[ChrisGreen]

Install is tomorrow morning, so any help on this would be greatly appreciated. Thanks.

[max+bank]

There was a good guide on here but a lot of the older posts seem to have been archived. 

I'm not an expert but this is what I did to get 4 eero working.

Advanced - WAN setup - enter the attached Deco  IP address as the Default DMZ server and select respond to ping on WAN port. 

For some reason iPv6 does not get translated through.

LAN Ip setup - others had turned off the DHCP server. I didn't as I lost access to the Sky router

Address reservation - the Deco IP address

Wifi - off

Have a go - I think that's everything but hopefully someone will add if I've got it wrong.

[Chrisee]

@ChrisGreen to have a voice line the Sky hub must remain as the first connection to the ONT. You have summarised the choices quite well. A double NAT set up works for most people without issue however some apps can object. You can simplify any firewall issues by placing your primary Deco unit in the Sky Hub's DMZ if you want. How that is done depends on which hub you get from Sky but assuming you have the white type the setting is in the My Sky app where you can turn off the wifi bands as well.

If your Sky Q boxes work with your current set up they should continue to with the switch but disabling the Sky hub's wifi is sensible. Personally I run a Deco set up in Access Point Mode myself and find the Sky hub's WiFi works pretty well as a router of course each system is different. 

[ChrisGreen]

They have sent me an SR203 (pointless paying for Sky's white router when I won't be using it for Wi-Fi). The SR203 is the same router I had for DSL from Sky before I went to Virgin during the pandemic.

It's that whole DMZ setup (which I did last time I was with Sky) that I don't remember how to do.

[ChrisGreen]

Hi @max+bank 

Thanks for the screenshots, really helpful. I did the whole DMZ thing the hast time I was with Sky Broadband, and it worked fairly well, but I can't for the life of me remember what I did, and as you say, no guides on here as they've either been archived or deleted.

[ChrisGreen]

I have, for now, switched the Deco to Access point mode and put the Sky router in charge of DNS. So no double-nat for now, but seeing whether the loss of QoS on the Deco mesh is a noticeable problem or not. If it is I'll go back to the Deco as DNS, and do the DMZ config on the Sky router.

[max+bank]

I'd tried the access/bridge on the eero and it does allow iPv6 to pass through that way. I have a Plex server attached to one eero  which needs external access and wasn't sure how the port forwarding would work on the SR203 to the eero, so have gone the DMZ route for now. 

[Chrisee]

@ChrisGreen on the SR203 the DMZ setting is in the hub's web inerface at 192.168.0.1 log in with user admin and the wifi pasword on the label. You dont need to use the DMZ in a double NAT setup its a refinement if you hit firewall issues.