@David-TP 

Hi,

The TP link router connected to the modem is Archer AC1750 (Archer C7 V2) . My internet connection requires PPOE. Initially i had the main deco connected to the modem and configured the main deco to work with PPPOE. I thought that the issue was related to main deco authentication procedure. I was trying to see if the issue is related to main deco PPoE and i added the archer to the network with the only job to perform the PPoE authentication.

The deco is configured to work as router. It will take IP from the tp link router. The purpose of purchasing the deco was to use the easy mesh. I did not disable the easy mesh as without the easy mesh it doesn't bring any value. Can the deco's be configured as access points and still have the easy mesh functionality ? (e.g., same WIFI network, easy transition from one deco to another)

I actually disabled the leds but when i go to the deco app i do see a big error saying no internet connection, check your ISP provider. 

The network topology is:

Internet----TP-Link router----main Deco X55---satellite Deco X55#1

                                                                    \---LS1005G---2 *other satellite; 1 satellite Deco X50 + 1 satellite deco X55

Another topology I used that reprdoduced the issue is the one below.

FYI: today i only have Decos connected to the switch. The other devices are connected to the TP link router directly:

The old network topology was:

Internet----TP-Link router----main Deco X55---satellite Deco X55#1

                                                                    \---LS1005G ---2 *other satellite; 1 satellite Deco X50 + 1 satellite deco X55

                                                                                        --- 2 other devices (a TV and a Hikvision NVR)

I also managed to reproduce the issue once by removing the cable from the deco x50 satelite. All others were connected via cable while this one was connected via WiFI to the main deco. All decos are configured to use the main deco as primary deco.

  @Bogdan_TP 

I am adding another update in the hope that someone will help me find a solution.

I disabled Easy Mesh on  Deco and the issue still occurs once every few days.  I noticed that when the issue is reproduced the Deco satelitess are shown in the application with the no network icon. When i disconnect one of the decos connected to the switch, the main Deco has again internet connectivity and shows all other satelites (except the one disconnected) with icon connected via WIFI. After a few minutes it will show connection via Ethernet.

Maybe is worth mentioning that the deco i am disconnected is the only one that is not in WIFI range to the main deco. All other satellites can connect to main deco via WiFi and Ethernet. I choose Ethernet cable because the WiFi signal to the sateliltes is weak.

Does Deco provide any kind of logs that i can check ?

Is it possible to disable deco connection to main deco via WiFi and force it to work only via ethernet ?