topic Re: ZTE MC801A B12 update : Bridge mode broken in Broadband

ZTE MC801A B12 update : Bridge mode broken

Gagandeep — Tue, 18 Oct 2022 23:04:19 GMT

Hi there,

Community / Three moderators, I am hoping you can help me.

I have a ZTE MC801A which I have been very happy with for about a month. I run the router in bridge mode, meaning that another device can take the internet connection and distribute it via my own TP Link router.

A forced update to firmware B12 has broken this functionality, and my entire home network and hardware setup is now left completely non-functional. The ZTE MC801a has become completely unable to handoff a WAN DHCP address and as such I am forced into using the ZTE router, meaning my heating/lights/raspberry pi and VOIP phone are all offline as they are wired to my TP Link Router - the ZTE router doesn't have enough RJ45 ports

Is there a firmware update on the horizon to fix this? This is an absolutely basic function (and offered by all the major ISPS like virgin/BT etc) I am considering making a formal complaint to have the router replaced with the NR5103E as this can actually bridge its connection. In lieu of this, does anyone have any ideas as to what could have happened? All of these problems have coincided with the update on the 14th of October 😞

Re: ZTE MC801A B12 update : Bridge mode broken

JonathanB — Thu, 20 Oct 2022 09:49:13 GMT

Hey Gagandeep,

Welcome to the Three Community. I'm really sorry to hear of all the disruption this has caused to your home network.

I've brought this to the attention of a device specialist yesterday. I've been advised that bridge mode was tested with the last firmware update ahead of the general release, however we're getting that double checked for you. I'll let you know when I get any further feedback.

Thanks,
JonathanB

Re: ZTE MC801A B12 update : Bridge mode broken

Gagandeep — Tue, 25 Oct 2022 23:46:15 GMT

Thanks for looking into this JonathanB

I've moved everything around and am currently using the ZTE to handle my WiFi clients, but would absolutely look to using bridge mode again with a more advanced router of my own choosing. I think someone else has also had this problem and had posted about it in this thread

https://www.ispreview.co.uk/talk/threads/zte-mc801a-review.37993/

Re: ZTE MC801A B12 update : Bridge mode broken

JonathanB — Wed, 26 Oct 2022 13:15:05 GMT

Hey @Gagandeep,

I'm waiting on further feedback but just wanted to update you as best as I can for the moment. I've been advised the firmware update didn't make any changes relating to bridge mode.

I was informed that various settings including bridge mode are tested ahead of the general release of new firmware, so if the update has caused this issue, this doesn't seem to be intentional, and the issue didn't crop up during our tests.

I'll let you know as soon as I learn anything else.

Thanks,
JonathanB

Re: ZTE MC801A B12 update : Bridge mode broken

speacock — Fri, 28 Oct 2022 04:42:48 GMT

I have the same issue with the recent firmware update to the MC801A. I used to use mine in bridge mode with a Pfsense firewall but as soon as the firmware update was applied on 17th October it stopped working in bridge mode and will only work in router mode. If the bridge mode function is unchanged then I suspect the problem may be with either the DHCP server or with the NAT implementation. In bridge mode the MC801A used to pass the IP address of its WAN interface to the firewall (as expected) bit it now passes an address in the 192.168.0.0/24 subnet, which is what you'd expect if it was working in router mode. Router mode does work but it means you are using double NAT which breaks some services and also slows down performance by about 30%

Re: ZTE MC801A B12 update : Bridge mode broken

Gagandeep — Sun, 30 Oct 2022 17:57:48 GMT

Thanks for your input. This is exactly the same behaviour that I have discovered after doing some digging around.

I would think the only solution is anothrt firmware update, or the option to roll back.

Re: ZTE MC801A B12 update : Bridge mode broken

JonathanB — Tue, 08 Nov 2022 10:04:45 GMT

Hi @Gagandeep,

Sorry for the delay coming back to you on this. I've received word back from a device specialist that they've completed tests on bridge mode with the MC801a and aren't running into these issues.

We have not been able to specifically test a TP Link router in this set up, but we're not finding any problems with using other routers in our tests.

Is there any other hardware you can test instead of the TP?

Can you clarify when you say non-functional also? My understanding from experience and as described by speacock is that you may run into a double-NAT which isn't ideal, but still provides connectivity. Are you losing connection entirely due to this issue?

Thanks,
JonathanB

Re: ZTE MC801A B12 update : Bridge mode broken

speacock — Tue, 15 Nov 2022 10:06:42 GMT

Hi @JonathanB, obviously I can't speak for @Gagandeep, but by non-functional I mean it doesn't work at all, there is no internet connectivity now when in bridge mode. When in bridge mode with the new firmware, the ZTE device issues an invalid IP address to the router that is on its LAN interface, it issues an RFC1918 compliant address (default 192.168.0.1) this cannot work because it is not internet routable. Under the previous firmware, the ZTE device would pass the IP address of its WAN interface to the router that is on its LAN interface, it did not route, it just passed packets unchanged and the router that you place on the LAN interface communicates directly with the WAN rather than traversing another router and undergoing NAT.

I'd be interested to know if the person testing at your end is seeing the same thing - does their router pass the WAN IP address to the router on the LAN interface or does it pass the 192.168.0.1 address?

The issue is not confined to a TP-LINK router, I have the same issue and that's with PFsense not with a TP-LINK device.

Re: ZTE MC801A B12 update : Bridge mode broken

EngineerMelissa — Tue, 15 Nov 2022 14:26:16 GMT

Hi @speacock,

When you say it does not work at all, does this also mean if connected directly to the ZTE router you are not able to connect to the internet?

In the case of getting a RFC1918 address from the ZTE to your own router (Double NAT), this in theory should work even if it's not the current ideal situation. So just to confirm you cannot access the internet via this double NAT setup?

Thanks,
Melissa

Re: ZTE MC801A B12 update : Bridge mode broken

speacock — Sat, 19 Nov 2022 12:27:51 GMT

Hi, that is correct, there is no connection to internet when the ZTE is in bridge mode, it only works when set to its ‘Wireless broadband’ mode. In bridge mode it just issues the wrong address on its LAN interface and the bridge mode function stops working because the router that is on that interface is now trying to use a non-routable address. I haven’t tried it, but I suspect that if I manually configured the WAN interface on my firewall with the IP address of the WAN interface on the ZTE, it would probably work, but this would only work temporarily until the next time the IP address changed.

Re: ZTE MC801A B12 update : Bridge mode broken

Gagandeep — Wed, 28 Dec 2022 03:48:53 GMT

Still no progress with any kind of router working in bridge mode. Tried an asus, no dice.

Router is now dropping connection every day. Not impressed.

Re: ZTE MC801A B12 update : Bridge mode broken

Tdichello — Sun, 05 Mar 2023 19:28:08 GMT

Did you ever find a fix for this as I am having the exact same issue?

Many Thanks

Re: ZTE MC801A B12 update : Bridge mode broken

pyro1son — Tue, 21 Mar 2023 10:30:59 GMT

Any update on when there will be a fix for this as not being able to use Bridge mode is causing problems on my home network

Re: ZTE MC801A B12 update : Bridge mode broken

Willow2492 — Sat, 01 Apr 2023 23:04:07 GMT

I'm also experiencing this issue, are there any updates?

Re: ZTE MC801A B12 update : Bridge mode broken

speacock — Mon, 17 Apr 2023 05:35:29 GMT

I've heard nothing since my last post, but the B15 firmware update seems to have caused the issue to become more widespread. There's a comment from @JonathanB on another thread that suggests there may be a fix - https://community.three.co.uk/t5/Broadband/Bridge-and-Public-WAN-failure-MC801A-B15/m-p/10186#M1494

Re: ZTE MC801A B12 update : Bridge mode broken

JonathanB — Tue, 18 Apr 2023 16:11:33 GMT

Hi @speacock,

Sorry for the considerable delay in updating on this one. I think we may have made some progress recently.

Can you, and any others running into this issue check your APN settings and let me know which Three APN you're connecting on?

It should be set to "3internet", but if you have "three.co.uk" saved instead, this could cause the IP error described on this thread. The three.co.uk APN should only be triggered when using a phone plan SIM (or if manually entered), but I'm wondering if the firmware update may have reset the APN.

You ought to be able to check/edit this in the router admin pages, there'll be a section for "My router", then APN can be set to Manual from there.

Please let me know if this seems to be relevant to this issue.

Thanks,
Jonathan

Re: ZTE MC801A B12 update : Bridge mode broken

oiskosminhos — Tue, 25 Apr 2023 15:50:29 GMT

I'm having the same issue as speacock. ZTE MC801A is not passing on the WAN IP when configured in Bridge mode, even when connected to my laptop. Looks like I'll have to return this.

Re: ZTE MC801A B12 update : Bridge mode broken

speacock — Wed, 26 Apr 2023 13:23:15 GMT

Hi Jonathan, mine is set to 3internet already:

I'll try changing it from Automatic to Manual though and see if that makes any difference

Re: ZTE MC801A B12 update : Bridge mode broken

speacock — Sat, 06 May 2023 13:47:38 GMT

@JonathanB As mentioned before, my APN was set to 3internet but was set to Auto, I've just changed it to manual and then manually set the APN to 3internet (so ostensibly no difference in the actual setting) and sure enough, when I switched it back to bridge mode it is now working again. So it seems like, even though it says it is using the correct APN when set to Auto mode, it actually isn't. Either that or manually setting that particular setting causes another one to be reset.

Whatever the cause, it resolves the issue and I now have my own firewall working properly, no double NAT and performance back up to 930/135 where it had been 500/100 without bridge mode.

Re: ZTE MC801A B12 update : Bridge mode broken

JonathanB — Wed, 10 May 2023 10:30:13 GMT

That's great to hear @speacock, I'm sorry it's taken so long to make progress with this. Hopefully some other users can confirm if this is a consistent fix for them too. Please let me know how it's performing after a few days with this set up.

Thanks,
Jonathan