Zyxel NR5103E - IP Passthrough Unable to get Wan IP only internal 192.168 address - Unifi UDM PRO SE

[aronanbo]

Hi all I have just joined 3 Mobile in the UK and currently have a UDM Pro SE.

I have moved my primary connection which is 80/20 Mbps to the secondary and wanted to use the three 5g routers in (IP passthrough / Bridge mode ).

I cannot get it to give me the wan IP or any service.

Do you have any help or suggestions?

It keeps giving me a local or no IP. it works connected directly to my PC via ethernet giving me a wan IP but no luck with the UDM

https://www.reddit.com/r/Ubiquiti/comments/15iahyz/unifi_dream_machine_se_three_mobile_5g_nr5103e_ip... 

https://community.three.co.uk/t5/Broadband/Eero-5-Wifi-Mesh-NR5103E-IP-Passthrough/td-p/10099 

https://community.three.co.uk/t5/Network/Zyxel-NR5103E-IP-Passthrough/m-p/7467 

https://support.zyxel.eu/hc/en-us/articles/7254914487186-How-to-put-my-router-in-Bridge-mode 

[db12]

This was working absolutely fine until recently, I cross posted to Is preview

Post in thread 'New Three 5G Hub (NR5103E)' https://www.ispreview.co.uk/talk/threads/new-three-5g-hub-nr5103e.38663/post-316282

[db12]

Just found this, seems IPV6 has broken passthrough:

https://community.three.co.uk/t5/Broadband/Zyxel-NR5103E-no-longer-get-public-IPv4-address-how-do-I-...

[jezza007]

Same symptom has just happened to me on 24.09.2023 
I have a Huawei H122-373 on firmware 11.0.2.11(H329SP4C21)
It's been on this firmware for as long as I can recall since around August 2022 I think it updated.
It's been working absolutely rock solid on bridge mode until 24th Septmeber 2023, 
Absolutely appauling, that something clearly has changed on three network, as nothing has changed my side, I run a tight ship on my firewall. 
I have factory reset the Huawei, and still no joy.
I will investigate further and recreate the APN to use IPv4 only and see if that fixes it.

[jezza007]

Got no idea why this suddenly stopped working, but heres an update on how I resolved it.

1. Disconnect all network cables from modem
2. Factory reset the modem
3. Connect using default wifi password
4. Set to bridge mode
5. Restart modem
6. Ensure your firewall is already powered up then connect Ethernet to LAN port
7. Only now did it get correct WAN IP address
   
   Several attempts of factory reset in any other order/method failed with 192.168 address getting locked in

[bazantus]

Hi,

non-techie here trying to get my head around it. Can somebody kindly put step-by-step instructions for Zyxel NR5103E to ack as a modem / bridge and feed into a Synology or Asus router (so all WiFi traffic, firewall etc is done on Synology)?
I keep running into issues with IP addresses, WAN and LAN addresses.
WWW has a few suggestions - but either incomplete or contradictory (e.g., some say you need to disable IPv^, some suggest to disable firewall - but no details how).

thanks!

[bazantus]

one other question is how to ensure it's Lan-Wan (os should it be?)