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BT doesn't support port forwarding

Jaysnp101 — Fri, 15 Oct 2021 11:07:29 GMT

I spoke to BT this morning and they say they don't support port forwarding on the Smart hub 2?

Is this true?

While upnp will open ports 3659, 9308 UDP they are never open. Even when running the program.

Port forwarding has zero effect too.

Only port that is ever open on the device is 9295 which isn't on the UPNP list or port forwarded.

Anyone have any idea how to fix this please. Thanks

Re: BT doesn't support port forwarding

licquorice — Fri, 15 Oct 2021 11:18:47 GMT

The SH2 does support port forwarding, no idea why you were told it doesn't.

Factory reset the hub, turn off Smart Setup and UPnP and try again. It is best to disable UPnP if port forwarding.

Re: BT doesn't support port forwarding

Jaysnp101 — Fri, 15 Oct 2021 11:32:47 GMT

I don't think a lot of their staff have a clue tbh, or they just find it easier fobbing people off.

I have tried factory reset and disabling upnp already but nothing helps.

For some reason I don't have the option to disable smart setup on my router.

I log in and the option has been taken away 🙃

Even with port forwarding set up or upnp enabled I get the same result. Only port open is 9295 .

Re: BT doesn't support port forwarding

Jaysnp101 — Fri, 15 Oct 2021 13:21:37 GMT

I'm certain there is something wrong.

I can literally factory reset most devices in my house along with the SH2 but all the devices with retain their previous IP address like it is stored elsewhere.

My LAN ip's never change , static or dynamic it doesn't matter.

I have so many problems but nothing ever gets sorted.

Re: BT doesn't support port forwarding

Keith_Beddoe — Fri, 15 Oct 2021 13:25:59 GMT

@Jaysnp101

Devices will not change their IP address, unless they request a new one. You have to factory reset the home hub to remove any stored IP entries, a normal restart does not do that.

Re: BT doesn't support port forwarding

Jaysnp101 — Fri, 15 Oct 2021 13:54:57 GMT

Sorry @Keith_Beddoe I did mention in the last message that I can factory reset all devices in my house including the SH2 and they will retain their original IP's.

Any reason why?

Re: BT doesn't support port forwarding

Keith_Beddoe — Fri, 15 Oct 2021 14:01:41 GMT

@Jaysnp101 wrote:

Sorry @Keith_Beddoe I did mention in the last message that I can factory reset all devices in my house including the SH2 and they will retain their original IP's.

Any reason why?

I do not use a BT Home hub owing to similar issues in the past, so you will have to see if someone else can offer some help.

Re: BT doesn't support port forwarding

licquorice — Fri, 15 Oct 2021 14:13:46 GMT

There has to be an algorithm somewhere that seeds how DHCP allocates IP addresses, it probably just allocates the same ones each time the hub is factory reset. Why does it matter?

If you want to be totally in control of IP addresses, simply turn off DHCP on the hub and allocate the addresses manually on each device.

Re: BT doesn't support port forwarding

Jaysnp101 — Sat, 16 Oct 2021 13:23:08 GMT

Yeah I agree there must be an algorithm holding the devices that were connected along with their IPs but what other information are they holding onto?

Could be why upnp and port forwarding doesn't work properly.

Surely outside of the router though they shouldn't be holding that information?

Re: BT doesn't support port forwarding

licquorice — Sat, 16 Oct 2021 13:27:41 GMT

I have no idea why you consider devices keeping their IP addresses a problem. It is essential that they do if port forwarding is to work.

All I can say is port forwarding works fine for me on an SH2, so its not a general problem.

Re: BT doesn't support port forwarding

Jaysnp101 — Sat, 16 Oct 2021 13:58:03 GMT

Me considering it a problem or not is totally irrelevant.

When I FACTORY RESET a device I don't expect it to withheld any of my information locally or externally.

I agree it may not be a general problem that everyone has issues with but I guarantee I'm not the only one as I've seen numerous posts with simular problems.

Re: BT doesn't support port forwarding

Jaysnp101 — Tue, 19 Oct 2021 13:13:49 GMT

This issue is literally impossible to resolve now.

I honestly think bt are using their 172.16 address range (private) to help with the ipv4 problem. 172.16 is a private ip range so uses NAT which results in me having a double NAT.

This is the only reason my port forwarding , dmz and upnp never works.

I've contacted bt and they aren't being very helpful to say the least.

I feel like ofcom is the only route forward now as this is far from acceptable.

Re: BT doesn't support port forwarding

licquorice — Tue, 19 Oct 2021 13:28:37 GMT

Your public IP address is not in the 172.16 range, the gateway is. You are not double natting.

Re: BT doesn't support port forwarding

Jaysnp101 — Tue, 19 Oct 2021 14:12:30 GMT

The default gateway uses NAT

Re: BT doesn't support port forwarding

licquorice — Tue, 19 Oct 2021 14:16:39 GMT

Sigh, incoming connections don't use the gateway address, they use your public IP address.

The 172.16 address is the BT BRAS

Re: BT doesn't support port forwarding

Jaysnp101 — Tue, 19 Oct 2021 14:55:16 GMT

When doing an IP trace it shows my public IP 2 miles away from my house. Whilst my default gateway is on my doorstep.

Re: BT doesn't support port forwarding

licquorice — Tue, 19 Oct 2021 15:07:50 GMT

https://whatismyipaddress.com/

Will tell you what your IP address is, it will be the same as your Broadband IP address shown on your hub.

Re: BT doesn't support port forwarding

Jaysnp101 — Tue, 19 Oct 2021 15:23:14 GMT

Yeah it was the same when I checked in the past.

So whats stopping bt issuing public ip addresses to everyone then having all these BT BRAS on the edge of their network which have private addresses. Which on essence creates a double NAT anyway? Maybe not on inbound connections but outbound?

Re: BT doesn't support port forwarding

licquorice — Tue, 19 Oct 2021 15:52:07 GMT

BT does issue public IP addresses to everybody.

It doesn't create a double NAT, it is just the first hop from your router.

Trust me, none of this has any relevance to your problem.

Re: BT doesn't support port forwarding

Jaysnp101 — Tue, 19 Oct 2021 16:12:10 GMT

I honestly think it does.

What else would prevent me using port forwarding and upnp effectively.

I've even tried the W9980 router with same result.

The 172.16 subnet is a private address so its not even connected to the WAN at this point.