New Customer Experience with Port Forwarding

Question

OK, so my OpenReach Modem and HomeHub 3 were installed last week and all seemed OK at first.
A bit of background:
I'm a seasoned IT guy and have a nice network set up at home that caters for my needs (most of the time).
Without going into too much detail, I have my own DHCP/DNS server and I run a Webserver for personal use.
I have Virgin Broadband - which work most of the time.
I've also just had BT Infinity installed so I should always have Internet access no matter which ISP is having issues.
I was hoping to be able to access my webserver externally from either my BT or Virgin. I didn't think this would be an issue.
It still all works fine through my Virgin connection. I use dynamic DNS (no-ip.org)  to get to my server. 
On the Virgin Superhub - I have DHCP switched off and all my machines (except one at the moment) get the Virgin router assigned as the Internet gateway (via my own DHCP server).  
My test machine gets a the BT HomeHub 3 assigned as the Internet gateway (also from my own DHCP server) and I have switched off DHCP on Home Hub.  
Before I move onto my issue, I have to say that the above network setup works flawlessly. 
The Virgin Router is on 192.168.0.1, The Home Hub is on 192.168.0.2.  (subnet 255.255.255.0)
They are on the same network but because DHCP it switched off on both routers - everything is happy.
I can access my Server from the Internet via my no-ip.org address and it all works great.
The issue:
I thought it would be relatively simple to configure the BT Home Hub 3 to access my server from the Internet.
Hmmm. Port Forwarding seems to be the issue. It just doesn't work reliably enough. Sometimes it works, then sometime it stops working. Right now it's not working.
At first I though it was just me, not configuring it correctly. But no.
Then I started reading this forum and found there are reports of issues with port forwarding going back a year.
I don't know if that a good or bad thing - an issue running that long must be on the verge of getting fixed right?
Or any issue running that long without resolution probably has no simple resolution or just isn't a priority (for BT) maybe.
My Question:
(and I think I already know the answer)
Has anyone got a sure fire way of configuring the HomeHub3 so the port forwarding works? 
Or should I just throw in the towel now and buy a Dual Wan Router? 
One last note:
This morning my Infinity Broadband Speed dropped from
38Mb down/6Mb Up (measured several times yesterday)
to
0.7Mb down/0.3Mb Up (yes those decimal points are in the right place)
And I haven't got a clue why.
I power cycled the HomeHub and it returned to normal. Does this happen to other people?
Cheers
Graeme.
Graeme

Answer 1

Bullitt wrote:
the port on your network is defined by lan ip address and port number eg 192.168.1.10:80
you cannot forward this outbound port twice
There is no "port on my network" A port is associated with a IP address not a network.
My webserver listens an port 80 - requests from the Internet for http are port forwarded by the router (either BT Homehub or Virgin Superhub) to port 80 at address 192.168.0.5 (in my case). 
If I am trying to access my webserver from the Internet, I point my browser at the WAN IP address of my router (again it doesn't matter which one - BT or Virgin) and the router port forwards the request to my Webserver.  Each router can do this independently. 
"you cannot forward this outbound port twice"
As explained above - It's an inbound port not an outbound port.
I appreciate you are trying to be helpful but just telling me something is not possible without explaining why its not possible doesn't really help me.
As I said before, this was working fine, then it stopped working but only when trying to access my webserver via the BT Router. It still works fine from my Virgin Router. I used WireShark and port mirroring on my switch to prove that the Home Hub as stopped port forwarding inbound traffic to my webserver. 
This is a problem with port forwarding on the Homehub, not my network setup. Looking at other posts on this forum - I'd suggest I'm not the only one having problems.
To be honest, it's the least of my problems with the HomeHub right now. I'm far more concerned with the fact that twice today I've had to power cycle it because the throughput has dropped from 38Mbit-down/6Mbit-up to <1Mbit-down/<1Mbit-up. It's a known problem, BT are working on it, yet I still am paying full price for a product that should never had made it out of Beta test.
Graeme