Connecting OPNSense to FTTP ONT

I'm currently on FTTC and I use a DrayTek Vigor 130 as a modem feeding into an OPNSense router/firewall.

I'm moving to FTTP and I'm unsure whether I still need a modem. Can anyone please advise whether I can connect the OPNsense box directly to the Openreach ONT or whether I need to use the ISP-supplied router in modem mode as a link between OPNSense and the ONT?

Edited by ashdown (Mon 29-Jun-26 21:16:21)

In reply to a post by ashdown:

I'm currently on FTTC and I use a DrayTek Vigor 130 as a modem feeding into an OPNSense router/firewall.

I'm moving to FTTP and I'm unsure whether I still need a modem. Can anyone please advise whether I can connect the OPNsense box directly to the Openreach ONT or whether I need to use the ISP-supplied router in modem mode as a link between OPNSense and the ONT?

You can connect it direct via the port you have configured as your WAN.

No modem needed as the ONT will be your modem

Thanks to both for confirming this - much appreciated.

In reply to a post by PCJM40:

In reply to a post by ashdown:

I'm currently on FTTC and I use a DrayTek Vigor 130 as a modem feeding into an OPNSense router/firewall.

I'm moving to FTTP and I'm unsure whether I still need a modem. Can anyone please advise whether I can connect the OPNsense box directly to the Openreach ONT or whether I need to use the ISP-supplied router in modem mode as a link between OPNSense and the ONT?

You can connect it direct via the port you have configured as your WAN.

Yes, I just unplugged my router cable from my HG612 modem and plugged it into the ONT. I did not make any changes to the router. The router connected to Plusnet using PPPOE without my making any changes and I also kept my fixed IP address.

Yes, I just unplugged my router cable from my HG612 modem and plugged it into the ONT.

But never link the modem direct to the ONT, else you’ll create a data infinity loop, and shortly after, mankind will cease to exist. *






* or you’ll lose wifi. (It’s one of these two anyway)

In reply to a post by Michael_Chare:

Yes, I just unplugged my router cable from my HG612 modem and plugged it into the ONT.

technically the hg612 is a router modem, if your hg612 was unlocked you'd see the router functions..

mind you, u'd be a bit silly to use the router function of 612.........

In reply to a post by Taras:

mind you, u'd be a bit silly to use the router function of 612.........

Rather underpowered device; with only a VDSL WAN port, so yeah, technically possible, but useless for most people!

In reply to a post by jchamier:

In reply to a post by Taras:

mind you, u'd be a bit silly to use the router function of 612.........

Rather underpowered device; with only a VDSL WAN port, so yeah, technically possible, but useless for most people!

hugely underpowered and anything that is underpowered, is a security risk to varying degrees. Hence me saying its silly to run it in router mode.