ZTE MC801A B12 update : Bridge mode broken

[Gagandeep]

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 😞

[JonathanB]

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

[Gagandeep]

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/

[JonathanB]

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

[speacock]

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%

[Gagandeep]

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.

[JonathanB]

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

[Gagandeep]

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.

[speacock]

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.

[EngineerMelissa]

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