Asus DDNS Double NAT Sky ER115 Help

malford

Hello.
I need some networking wizards help please sorry its a long post.

I have been a Sky fibre 40/10 customer for the past 6 years using the supplied BT Openreach modem and an Asus AC87U router using a cloned mac address of the original Sky Sagem router and running Merlin option 61 firmware. This service only dropped once in 6 years and was very reliable and stable.

Dell PC      ---------|
QNAP NAS ---------| ----- Asus AC87U Router ---- Huawei Echolife HG612 3B ----- Internet
Hikvision CCTV ----|

The setup above allows me to use the embedded DDNS on the Asus router which is shared to a Neighbour Hood watch scheme and works extremely quick.

I recently upgraded my package to the Sky Fibre 80/20 service and was given a ER115 router which is quite frankly rubbish this was kept connected to the ISP for 10 days whilst they carry out QoS and stability checks.
The only problem with this setup is Im now behind a double NAT and I cannot use the Asus embedded DDNS service and I get the following error message:

"The wireless router currently uses a private WAN IP address. This router may be in the multiple-NAT environment and DDNS service cannot work in this environment."

Dell PC      ---------|
QNAP NAS ---------| ----- Asus RT-AX88U Router ---- Sky-ER115 ----- Internet
Hikvision CCTV ----|

I have tried to put the ER115 into Bridge or Modem mode but this is not possible due to firmware restrictions, my next try was creating a DMZ but for some reason the Asus DDNS would not work.

So I have copied the ER115 mac address and entered it into the Asus RT-AX88U WAN page in the same way my previous setup was but without the Merlin option 61 username & password as this is no longer required and re-connected the BT Openreach modem

Dell PC      ---------|
QNAP NAS ---------| ----- Asus RT-AX88U Router ---- Huawei Echolife HG612 3B ----- Internet
Hikvision CCTV ----|

This setup works great and Im getting 7ms ping 74.8mb down & 18.74mb up and the Asus DDNS is back up and running...
This has worked for 6 days without any drops or issues but recently the service keeps getting disconnected at 02.00 to 04.00am and again between 14.00 to 16.00pm.
I have spoken to Sky and they informed me it is very likely it is when they are carrying out checks... so Im thinking the ER115 has some way of calling home and when Sky dont get a response it resets the line automatically and then drops the Asus/BT modem connection?
The only way of getting the Fibre connection back online is to reconnect the ER115 until I have 3 green lights then disconnect DSL plug and plug it back into the BT modem and then reboot Asus and all is good until they carry out another test..

So my questions are:

1... Can I run the ER115 with modified settings that will allow the Asus DDNS service to work.

2... Install Merlin on the Asus RT-AX88U and enter the Sky option 61 username even though it works with standard Asus firmware and just a cloned mac address.. the downside of running Merlin is I will lose the AiMesh capability.

Incidentally since March I have had 3x Openreach engineers do extended tests on my setup and all found no faults with my setup.

psychopomp1

I think Sky are telling you porkies. Once Sky have activated your vdsl2 line, the Openreach DLM system (sitting in your FTTC cabinet) takes over the running of your line. Any disconnections will be down to the DLM as it constantly (24/7) monitors your vdsl2 line. The Sky agent may have got VDSL2 & ADSL2  mixed up, Sky do have more control on the latter as Sky use their own DLM system but obviously you're not on ADSL2 . So the question you should be asking is, why is the DLM disconnecting you at certain times of the day? My guess is excessive noise on the line which is being created by something electrical being switched on/off during those times.

Regarding Q1, I'm not sure if the Sky modem/router can be modified? Even if you could, you're at the mercy of the Openreach DLM.

The only thing I can suggest is, perhaps try a different vdsl2 modem as different modems give different results. Worth trying out the Huawei HG612 (cheap as chips on ebay but still a rock solid modem) or the Draytek 130 modem. Or if you want an all-in-one modem router, then something like the TP Link VR2800 or Asus DSL-AC88U is highly recommended. You may get both Asus DDNS & AiMesh working on the Asus DSL-AC88U.

Edit: sorry realised you’re already using the hg612, in that case try the draytek 130 or the Tplink W9930 in modem only mode. I don’t think the sky router can be used in modem only mode.

malford

Thank you for your detailed reply
Yes Im already using the Huawei HG612 modem in tandam with a Asus RT-AX88U, It previously worked with the SkyFibre 40mb service for 6 years without any issues.

I am only a novice when it comes to network wizardry so tonight I have been fiddling with the advanced settings of the ER115 (192.168.0.1) and have setup a DMZ pointing to the Asus router (192.168.0.2).
Firewall: I have opened all ports on outgoing and incoming services on the ER115
Services: I have added all ports associated with the cctv system 80,443,8000,554 on the ER115
LANIP: I have turned off DHCP and reserved the Asus router to 192.168.0.2.

ON the Asus WAN connection type I have set to "static"
IP Address 192.168.0.2
Subnet 255.255.255.0
Default gateway 192.168.0.1
DNS Gateway 192.168.0.1

Everything works except the Embedded Asus DDNS service.... Im beginning to wish I never called Sky for the speed upgrade

                                                                       

psychopomp1

Those vdsl2 line stats look fine. As a last resort, you may want to revert to your previous hardware setup - Sky may be able to transfer your 80/20 line credentials to the Sagem router. TBH the Asus RT-AC87U is still a damn fine 802.11ac 4 stream Mu-Mimo router and unless you have 802.11ax (wifi 6) clients, its just as good as the RT-AX88U.

mickevh

Does the new Sky router offer DDNS..? If so, you potentially don't need the ASUS, or you could convert it to an AP.