Flint 3 - DOCSIS Modem WAN Broken on Some Firmware Versions

Router
1

Hi all,

I recently purchased a Flint 3 to replace an ASUS ROG GT-AX6000 that I’m repurposing. I remember when I initially set it up it came with firmware 4.7.x and the internet just would not work, even through it showed the WAN IP in the web interface. My setup is DOCSIS with Virgin Media in Ireland, using the Hub 6 in Modem Mode, which has always worked for me on my previous (primarily ASUS) routers. The Hub 6 is connected via its 2.5Gb LAN port to the WAN on the Flint 3, and the Flint is set to DHCP.

So I thought to myself, let’s see what happens when I flash to the latest firmware, which at the time was 4.8.3, and voila, via manual download and update, it worked. Since then I’ve had no WAN issues. I even flashed to 4.8.4 via the updater in the web interface and still no problems.

However, I was curious to see what the beta 4.8.99 firmware had to offer, so I gave it a go. And the WAN immediately stopped working. I can see in the interface again that the WAN IP shows up, sometimes, but then I reboot the modem and router, it may or may not show as connected thereafter (I can’t find a correlation).

What I’ve done to troubleshoot is perform a factory reset on 4.8.99 in case it was something I had done, which did not resolve the issue, and rebooted the Hub 6 and Flint 3 numerous times. I even tried configuring the WAN IP statically to no avail. There is no need to clone my MAC address as my ISP will provide an IP regardless, but I do clone my ASUS router’s MAC so I can keep the same IP I’ve had for the past 18 months using an identical Hub 6 setup and a decent, short, Cat6a cable. Clone vs. Default MAC, it made no difference on 4.7.x or 4.8.99.

Flashing back to 4.8.4 manually fixes the WAN, even when I restore a backup of my config in LuCI. I’ve flashed between the firmwares about 3 times and the result is always the same, but thankfully going back to 4.8.4 always brings the WAN back to life.

So in summary, on 4.8.3 and 4.8.4 there are never any issues linking with the Hub 6 for the WAN but on 4.7.x and 4.8.99, it was consistently broken.

I’ve seen some topics on this issue in the forum but what was different was there was no mention of it working on some firmware versions and not others, or there was no resolution posted.

Any ideas? Thanks, all in advance.

2

Hi

This appears to be a compatibility issue with the 2.5Gbps port on the Virgin Media Hub, which we fixed in Flint 3 v4.8.3 and above.

But since v4.8.99 is a special beta firmware, that fix may not have been merged into it yet.

For now, please continue using the main release versions, such as v4.8.3 or v4.8.4.

4

Ah! The only thing I didn’t try was switching to one of the 1Gb LAN ports on the Hub 6.

I’ll give it a try later and post back.

Thanks for the super-quick insight and if it works with a 1Gb link, it may be of use to others if they come across this thread.

5

I tested out 4.8.99 again and consistently with the 1Gb port on the Hub 6 being used it worked and also continued to malfunction on the 2.5Gb port, so I’m confident that once the fix is merged into future releases all will be good.

It’s a good thing to note as well, in case some folks for whatever reason wish to remain on an older firmware and have the same issue.

Thanks again for the quick explanation, Will.