@LazyBrewer et al,

I contacted TP-Link Support over the weekend (Live Chat) and they had me change my DNS to manual entries (below), rather than automatically use those of my ISP.  After that change, saving, and physically rebooting every mesh, it 'appears' to have helped.  I'm still prepared to downgrade firmware if needed, but so far it hasn't been necessary.  I'm not technical enough to know how that's related, just sharing my own story and something to try. 
Greg

  @Greg_B That's a truly odd response from them. I'm not sure how using Google's public DNS servers would have any effect on a local mesh system. DNS is all about matching domain names to an IP address on an external server.

Are you seeing any of the satellite Decos drop off or has it completely eliminated the problem?

  @LazyBrewer , those were my thoughts exactly.  I'm still skeptical as that being the fix though, given what I saw happen.

It's been ~30hrs of uptime and no satellite drop-offs to my knowledge.

If/when you engage TP-Link support, already have gathered the physical LED behavior of each deco, it's likely they'll ask.

There's a related thread on the Community, I think both are chasing the same thing, called: "Deco X90 losing connection after 09/2022 firmware update"

https://community.tp-link.com/en/home/forum/topic/588102

In the course of all this, I also noticed (but not saying related, just calling out deltas) that I picked up a new and very different IP/gateway from Fios.  Wondering now in hindsight had I physically rebooted the ONT first, to accept any changes there, then physically reboot the whole mesh if that would have made any difference.

  @LazyBrewer 

So here to report no issues since I went back to 1.1.2 yesterday.  I've had TP-Link reach out to me wanting to put some diagnostic firmware on my units to try and figure out what the problem is.  I am maxxed out with work today so I cannot put my network back into "lunatic" mode - but if anyone has time today and doesn't mind being the guinea-pig Parker Hu from their support team seemed very keen on getting to the bottom of this (big thanks to TP-Link for actually having customer service..

On a aside - here is the email I sent to them describing my problem - if we all describe our setups it might help them narrow down the problem and get a solution deployed. 

 

Hey Parker,

 

I am in Germany. I will answer any questions you may have. I work from home and cannot have another day of the network going nuts.

 

What I've noticed about the problem (being able to replicate it) - all the people online complaining about this issue had both wireless backhaul and ethernet backhaul employed on their network. 

 

The Decos (so a x90, 2x P7s and a M5) that kept dropping were the decos connected to a X90 and that X90 connected to the main Deco base station.  My M5 and P7 that connect directly to the main X90 deco never dropped or had any issues. 

 

Restarting the entire network would not solve the problem, but relocating on of the "daughter" Decos would resolve the issue for a few hours before dropping started again.  So said another way - when the decos start dropping - if I would unplug on the X90s the other decos are connecting from and physically relocate it to somewhere else in the house, plug it in - once it registered on the network - the network would stabilize and everything would work fine for a few hours until the problems started repeating. 

 

I can gladly get you logs - but I am not sure if the logs would have survived the firmware flash back to 1.1.2

 

If I could guess (I am not exceptionally tech savy but am not a Boomer either) - it seems like the M5s and P7s (all with latest firmware) keep trying to find new shorter "improved" paths to the main deco and in the process some of the "daughter" x90s try to connect to these M5s and P7s to connect to the main base station.  As explained by example - I have a chicken ccop and have an old P7 in the Chicken Coop running the cameras and smart accessories therein. That P7 connects to the X90 in my laundry room and that x90 connects to the X90 in my living room and that x90 connects to the main deco in my Pantry. Before some of the drops, I'd see on my network map that the x90 in the laundry room had connected to the P7 in the chicken coop and that P7 had connected to another M5 80 meters away on the front of my house running my security cameras there. E.g. something in the new firmware caused the entire network map to invert - within a minute or two of seeing that I'd experience the drops which would last for anywhere from an hour to six hours before "fixing" themselves. 

 

Best, 

  @LazyBrewer how do you downgrade the firmware on the decos? thx.

  @Gatriel just to say in my case I also have a mixed network with X90 and M9+ decos, but the X90-ies keep disconnecting, not the M9+´s. I also have no wires, all WIFI.

  @MaxHeadroom That is good to know. 

How do they connect? I assume your x90 is your main deco, right? 

So if you have multiple x90s - are they all connecting directly to your main deco or connecting through one another? 

  @MaxHeadroom 

You download the 1.1.2 firmware from the TP Link website (under support - for EU-based devices its here - https://www.tp-link.com/en/support/download/deco-x90/#Firmware) and then you extract the bin file to your desktop or whatever folder you want to - then access your deco web-based control interface via https://tplinkdeco.net/ in your browser, click Advanced (middle of screen) -> System (left hand side of the screen) -> then click Firmware Upgrade. 

Wait a few seconds for it to populate all your decos - and then select X90 from the dropdown list and then select the bin file on your desktop. Their software does the rest. 

  @David-TP Why would Google's public DNS solve a problem with mesh satellites falling off a LAN? DNS simply matches domain names to external IPs on a completely different network. This seems like suggesting to use a chain saw to drive a nail. I'm truly interested in why this might be a solution, not trying to be snarky:)

Mark