BT Smart Hub 2 with TP Link Decos

[Tom52]

I needed to extend my WiFi coverage at home. I bought three TP Link Deco S4s to set up a WiFi mesh.

I already had a BT Smart Hub 2 which provided reasonable WiFi coverage and an Ethernet connection, via power line adaptors, to my upstairs office PC and a NAS. All worked well save for the limited WiFi coverage.

The S4 set up was straightforward. I wanted to keep the Smart Hub 2 as my router so l put the S4s into access point mode. The WiFi network seems reasonably stable and l’ve keep WiFi on the Smart Hub switched on since the TP Link app reports overlap is low.

The problem came when trying to re-establish the Ethernet connection between my BT Smart Hub and my office PC and NAS. Thinking it would be a breeze I plugged in everything as it was before adding the S4s but all l got was an error message “unidentified network, no internet connection”.

Try as l might l’ve not been able to crack the problem though l’ve spent far too much time trying ! I turned off Smart DCHP under Access Mode in the TP app thinking that might be conflicting with the Smart Hub router but it seems to have made no difference.

If anyone far smarter than me has any helpful suggestions to get a working Ethernet connection from my Smart Hub l’d be very grateful. As l say prior to setting up the S4s the Ethernet connection via power line adaptors and an unmanaged Netgear switch worked fine. Puzzled. 

[countrypaul]

Best to start with keeping things simple as possible. If you turn off all your S4s can you re-establish the Ethernet connection for you PC & NAS?  If so, does turning on the S4 units cause the PC to lose connection to your router, when, the first one, 2nd, or all of them? Are you using a separate SSID for the router & S4s?

If with the S4s off you cannot re-establish the Ethernet between router and PC, and assuming you have tried resetting the router, then check that the cables are correct and have active links from router to powerline adapter and powerline adapter to switch. Following that you need to try and reset the powerline adapters or resync them (I know very little about how they are configured).

[Tom52 · Accepted solution]

Many thanks. 
Went back to basics, as suggested, disconnected and reconnected network, adaptors and the WiFi mesh and thankfully everything seems now to be working. I may have confused the system by swapping  out an old BT Hub 5 which l used as an access point for an Ethernet switch, or maybe finally disabling Smart DHCP on the mesh did the tick. Anyway, fingers crossed. 
Happy New Year