Hi

I hope someone can help as I am pulling my hair out with this one :?

I have a 2862ac setup and working fine on VDSL with an O2 4G dongle (P/N: 1HUE3DWN) for failover when the DSL fails.

• - The DSL is 'Always On' on WAN1.
  - The 4G dongle is in the first USB slot setup as '3G/4G USB Modem(DHCP mode)' on WAN3 and is set to 'Failover' on WAN Failure if WAN1 disconnects.

All of the above works fine.

The problem is the DDNS is not updating for the 4G modem.

Whenever the WAN1 connects, the DDNS updates as it should but it does not update it for WAN3.

I seem to remember that in the past (a long time ago at a different job) I have only had 1 Dynamic DNS Setup which is set as 'WAN1 First' and this then updates WAN1 if available then the failover (WAN3 in this case) if it isn't. However this does not work and I think it is because it not detecting the external IP of the 4G modem? When set up like this and the DSL is down i get the following:

• 2018-12-20 00:23:44.5 >>>>> DDNS is updating. <<<<<
  2018-12-20 00:23:44.5 [@1:User-Defined] A= , H= dynusername, U= 1
  2018-12-20 00:23:44.5 WAN1 is not active, do fail over.
  2018-12-20 00:23:48.6 [@1:User-Defined] WAN IP not present

This is the same whether 'Determine WAN IP' is set to 'WAN IP' or 'Internet IP'.

If I set up a separate Dynamic DNS for both WAN1 and WAN3 using 'WAN1 Only' and 'WAN3 Only' (I have also tried it using 'First' or both in various combinations with the same results) and set 'Determine WAN IP' to 'Internet IP' then I get the below repeatedly:

• 2018-12-20 00:44:02.1 >>>>> DDNS is updating. <<<<<
  2018-12-20 00:44:02.1 [@1:User-Defined] A= , H= dynusername, U= 1
  2018-12-20 00:44:02.1 WAN1 is disconnect, will do fail over later.
  2018-12-20 00:44:02.1 [@1:User-Defined] WAN IP not present.
  2018-12-20 00:44:07.1 [@2:User-Defined] A= , H= dynusername, U= 1
  2018-12-20 00:44:07.1 [@2:User-Defined] WAN IP not present.

but if I change 'Determine WAN IP' to 'WAN IP' then it seems to work:

• 2018-12-20 00:41:30.7 >>>>> DDNS is updating. <<<<<
  2018-12-20 00:41:30.7 [@1:User-Defined] A= , H= dynusername, U= 1
  2018-12-20 00:41:30.7 WAN1 is not active, do fail over.
  2018-12-20 00:41:33.6 [@1:User-Defined] WAN IP not present.
  2018-12-20 00:41:39.6 [@2:User-Defined] A= , H= dynusername, U= 1
  2018-12-20 00:41:40.6 [@2:User-Defined] Updated successfully.

However, it is actually setting the Dynamic IP to 127.0.0.1 - so not much use!!

Full Specs:

• Model Name: Vigor2862ac
  Firmware Version: 3.8.9.2_BT
  DSL Version: 779517_A/B/C HW: A
  4G Dongle: 1HUE3DWN from O2
  Various DDNS providers tried including: ChangeIP.com and DuckDNS.org

.

Do you have a real-world public IP address on the 4G dongle?

I thought you were 'NAT-ed' these days, unless you paid lots of dosh, at which point you got a fixed public IP address (and then you wouldn't need DDNS)...

hornbyp wrote: Do you have a real-world public IP address on the 4G dongle?

I thought you were 'NAT-ed' these days, unless you paid lots of dosh, at which point you got a fixed public IP address (and then you wouldn't need DDNS)...

Just done some tests and it looks like you are right This means it is useless for incoming traffic, which is pretty annoying :x

Thanks for your help

But not really Draytek's fault

Piste Basher wrote: But not really Draytek's fault

No, definitely NOT draytek's fault. I realise my post might seem to be directing my indignation at Draytek but I was just annoyed at the fact that 4G dongles now, almost exclusively, operate using NAT (and more than a little annoyed at myself for not realising this :wink: ).

It certainly used to be possible to get a public IP address from the Three network which worked with DDNS. There are some instructions here which should help: https://www.proroute.co.uk/support/apn-settings/ . I had this working a few years back with one of the first Draytek routers to support USB modems on the Three network.