topic Re: Plusnet FTTP and pfSense in My Router

Plusnet FTTP and pfSense

crgbt — Sun, 14 Dec 2025 14:32:26 GMT

Hi all,

I've just moved from Plusnet FTTC to FTTP, and I have the ONT (Nokia G-010G-T) plugged directly into my configured WAN port, and everything is working fine; however, I was wondering if anyone else is using pfSense and can share their PPPoE interface settings - if any are more optimal than the defaults?

I've tried setting the MTU to 1500, but it looks like Plusnet doesn't support baby jumbo frames as trying to send a 1472 byte packet requires fragmentation, so I have my MTU at 1492, my MSS setting is left blank, and TCPmssFix is enabled (by default).

Edit: Also, what are you using for your gateway monitor IP? The auto assigned gateway doesn't respond to ICMP, so I am using 1.1.1.1 (which I also used on FTTC) - is there a more suitable IP to use on Plusnet's network?

Thanks,

crgbt

Re: Plusnet FTTP and pfSense

crgbt — Sun, 14 Dec 2025 16:00:56 GMT

I was wrong about the baby jumbo frames support - I couldn't get it to work, but I've seen a few posts suggesting an MTU of 1500 should work on the Openreach FTTP network. I switched my pfSense instance from using the if_pppoe kernel module to PPPoE via mpd5, then back to the if_pppoe kernel module again, and setting a 1500 MTU works perfectly.

I can't seem to edit the original post for some reason!

Re: Plusnet FTTP and pfSense

Dan_the_Van — Mon, 15 Dec 2025 18:34:17 GMT

@crgbt

Also, what are you using for your gateway monitor IP? The auto assigned gateway doesn't respond to ICMP, so I am using 1.1.1.1 (which I also used on FTTC) - is there a more suitable IP to use on Plusnet's network

The problem is there are not many internal host which respond to a ping, plusnet DNS were once the choice but changes occured in 2023 so they are no longer available.

So the conclusion of a previous discussion in 2023 is to use a public DNS site Link to thread , using DNS Benchmark Level 3 was selected.

Re: Plusnet FTTP and pfSense

crgbt — Mon, 15 Dec 2025 21:31:11 GMT

Thanks @Dan_the_Van, I was just about to purchase the new GRC DNS Benchmark utility, so I'll make sure Level 3's servers are on there to test against.