@TP-Link this is utterly unacceptable. 
 

I buy standalone routers to run a local wireless network and they are unable to function without a live internet connection! This is a MAJOR defect and a major side sign flaw that renders these product unfit for sale and not or merchantable quality. 
 

I have no interest in the reason - these devices MUST be able to operate in isolation. Otherwise I want my money back for all 4 of these devices as that are not fit for purpose. losing broadband is NOT a reason for my home automation to fail - that means I lose heating systems

and it is JANUARY!!!!! 
 

Tplink has known of this issue for at least 2 years. I want dates for an action plan for resolution. 

I live in a rural area, and just installed a deco S4 Mesh, (and am hooking up a wired back-haul) the isp often drops. loss if the internet, should not impact/disable the intra-net, (i.e. i should still be able to connect laptop to nas or local server). two seemingly good options previously noted, 1) After auto-sensing, stop polling and lock the Lan port. (on re-cableing, reboot the router), -- although another edgecase is loss of power and no internet after power restored. 2) add a WAN option similar to the current IPTV port selection.

This is not a feature but a bug fix - it disrupts normal usage and blocks internet traffic.

  @TP-Link running into this problem with a very long internet outage today, was really surprised to find TP-Link lacks the very basic functionality of having a dedicated WAN port, and would never have bought the mesh if I knew this at the time.

This effectively means for the duration of any internet outage I have no access to my wired devices (which are obviously wired for a reason).

This is pathetic - and I am being kind saying only this.

 

 

Just running into this same problem this week. This needs to be fixed to allow the option to manually select the WAN/LAN ports

  @David-TP 

Im internet Provider operator in Poland and we see that DecoM4 router is injecting to the our WAN Network its local traffic.

 

We temporary disconnect some customers unless they configure their routers according to terms and specifications of the internet stards which base thing in router is it's LAN and WAN port.

 

I've attached the screen of our HUAWEII GPON unit report.

  @TP-Link This is a major bug on your 4G failover, and you don't care about it. 

Didn't know about this when I bought. I'm sending my DECO X20-4G back for refund.

 

EDIT : just found this LAN stops working after unplug WAN cable from Deco X20-4G - Home Network Community (tp-link.com)

There is a beta firmware trying to fix things since april 2022 ?? why is it taking so long ?

  @TP-Link Can we not add an option to set which port we want to use as the wan port and which we use as the lan port?

 

I have seen on other systems and opnsense is like this where you can set the wan/lan port to a particular nic, but I have noticed they have the same problem that if your internet goes down, routing between local network can fail. only way i've got around it in the past is to use a linux based pc to provide dns, etc

  @Bigredfury 

As long as TP-link does not solve this "feature", there is no direct solution.

The only possibility for the network to work when there is no WAN is to put another router in front of the tp-link router and to use it as an access point.

Like:

ANY router --> Tp-Link --> Switch or any other device(s) via LAN or WiFi

 

My setup is something like:

 

New router	--> Switch	LAN --> TP-Link (as access point)	WiFi -->	Any Wi-Fi device(s)
		LAN --> Cable	Cable-->	Any UTP device(s)
		LAN --> Cable	Cable-->	Any UTP device(s)
		...	...	...

 

  @Bigredfury The solution will definitely be to reset and redo everything, and then you will have the same issue again as soon as your ISP goes down.

 

If I didn't live in a country where I can't return my Deco, I would have returned it as soon as possible, after finding out this fatal flaw. If you read all the comments in this thread then you know I'm not alone. Every customer sees this for what it is: a serious problem. TP-Link thinks they know better and that it is, in fact, a feature. It's a classic case of thinking you know a customer's needs better than they do.

 

I, for one, will never buy another TP-Link product.