NR5103Ev2 IP Passthrough mode

[RedSnowDonkey]

I have an ER605v2 router that brings in both a feed from my THREE router (NR5103Ev2) and another ISP, so I can perform load balancing and failover when one fails (two teenagers, TV over the internet, and two adults permanently working from home requires a bullet-proof set-up).

I know that the NR5103Ev2 has an IP Passthrough mode but I can't for the life of me get it working - it just continues to provide a LAN address (192.168.1.x), rather than a WAN one.

I know that it can work, as I actually had it working until today (since "fixing" it last week), but having to factory reset (to enable me to move it, put the wifi back on, and give my phone an IP address to try out a new external antenna in another part of the house) has set me into a "this thing doesn't bl**dy work again" tail-spin.

I can't remember what the magic steps were from last week (as initially I had the same "no WAN address" problem, but found the right settings... from memory a strange combination of changing the time server, switching off DHCP, and rebooting) and there's something I'm missing (perhaps a NAT setting or changing something other than "IP Passthrough" in the Broadband settings.

Does anyone have any words of wisdom, here (as I know it can work, just can't work it out)?

Thanks in advance (and hope).

[RedSnowDonkey · Accepted solution]

I continued tinkering and combining tips from the rest of the internet and finally got it working!

Here's how:

• From a factory reset, don't have your ethernet connected and connect via WiFi only.
• Change the Broadband to being IP passthrough (and it'll probably force you to log in again).
• Change the Broadband APN to 'three.co.uk'.
• Change Broadband Cellular WAN 1 to IPv4 Only.
• Check the clock settings (in Maintenance).
• Reboot the box.
• Connect your ethernet.

That now works for me... and I'm putting it here in case anyone else gets frustrated and stuck!

[andyvee]

It is the forcing of IPv4 that fixes it. If you leave IPv6 enabled you end up with a non public IPv4 address as the WAN address - 192.168.1.2. Three have known about this for many many many months now and still haven't fixed it.

You can leave Cellualr WAN1 as IPv4/IPv6 dual stack - just set the APN to 3internet IPv4 only.

[iDriver]

Thanks for this, you just got my CCTV working via the 5g network away from home.

[Derwent]

After hours going round in circles got my router working in Passthrough mode with this additional setting, thank you.

[BobF]

In the IP passthrough mode do you specify a MAC address?  Does passthrough disable the WiFi? What am I looking for in clock settings?  Have you any idea why changing the APN makes a difference?  Thanks!

[Graham]

Thank you, RedSnowDonkey, for posting your solution. It helped me to get my NR5103EV2 working smoothly since I also use a TP-Link ER605v2 router to manage my home network. I have now got my NR5103EV2 in IP Passthrough Mode and have high-speed internet access throughout my home network.

Now I would ideally like to turn off the WiFi service altogether on the NR5103EV2 because I have a TP-Link Mesh wifi which covers my home and I would prefer not to have an additional SSID showing up. But since setting IP Passthrough, I can no longer access the web configurator for the NR5103EV2 using ethernet. I can only access it using wifi.

So, if I turn off the wifi on the NR5103EV2, I will loose access to the web configurator altogether. Then the only way to manage the NR5103EV2 will be to factory reset it.

Do you have any suggestions as to how I can manage the NR5103EV2 in IP Passthrough Mode without using wifi. I have tried connecting an ethernet cable directly between my laptop, with a manually set IP address, and the second ethernet port on the NR5103EV2. No reply from the NR5103EV2 and pinging 192.168.1.1 does not get a reply. I also tried connecting my laptop to the NR5103EV2 with a USB cable, but it seems that the USB port on the NR5103EV2 is only for accessing files on a USB stick.

Any suggestions will be welcome.

[Graham]

I did some more experiments and read everything relevant that I could find on the Internet. Finally I found the solution.

I needed to change the LAN network address on the NR5103EV2. By default it was 192.168.1.1 which overlaps with my home network meaning that my TP-Link ER605v2 router could not communicate with that network located on the other side of the Ethernet cable linking the two units. The NR5103EV2 has a WAN IP address in the range 188.30.24.xxx

What I did was to give the NR5103EV2 a LAN IP address of 192.168.100.1 That was the only thing I changed and immediately after that, without even rebooting the unit, I was able to fire up the web configurator from any computer on my home network including my desktop which does not have WiFi at all. Communication with the NR5103EV2 is now via ethernet and I only have one ethernet cable linking between the LAN port on the NR5103EV2 and the WAN port on my TP-Link ER605v2.

So now I can turn off WiFi altogether on the NR5103EV2 and just use it as a 5G modem, which is what I intended when I purchased it.