BT Whole Home ethernet backhaul - not working

[dinsdalePiranha]

I have 3 x Whole Home Wifi discs.  Having recently built an outbuilding, I wanted to extend the Wifii coverage to the building due to the distance involved the standard wifi backhaul signal was poor (orange LED, 2.4GHz connection).   Having read that the Whole Home Wifi discs support an Ethernet backhaul, I've installed a CAT6 Ethernet cable between the outbuilding and the main house.  This plugs directly into the internet router,  as does one of the WH Wifi discs (Kitchen).  This cable works just fine, as tested by plugging a laptop in and validating connectivity.  I've then moved one of the other discs to the outbuilding, and expected it to use the Ethernet backhaul - but it's not working. 

I've tried resetting the disc to factory defaults, but still no luck.   Here's the current status - office is the relocated disc.

How do I force this disc to use the Ethernet backhaul?

Kitchen (Primary)   Uptime: 3 days, 12 hours, 55 mins, 59 secs IP Address: 192.168.0.104 Connection Status: Excellent Ethernet Status: Connected - Uplink Connection Type: Ethernet

Loft     Uptime: 3 days, 12 hours, 55 mins, 54 secs IP Address: 192.168.0.106 Connection Status: Poor Ethernet Status: Disconnected Connection Type: Wi-Fi (2.4GHz) Signal Strength: -77dBm Channel: 6

office     Uptime: 34 mins, 51 secs IP Address: 192.168.0.107 Connection Status: Poor Ethernet Status: Disconnected Connection Type: Wi-Fi (2.4GHz) Signal Strength: -80dBm Channel: 6

[Gary_C]

It should work . They should just get an IP address from the router and then work.

Do the disks work ok as a mesh over wifi ?

Are they appearing in the DHCP list in the router ?

[Sircoynie]

Just to confirm, you are 100% sure this is the standard BT Whole Home Disk set? Ironically and inexcusably the premium whole home kit still doesn't fully support an ethernet backhaul and BT are being pathetic at updating it (even though it was advertised as having this feature!!!). 

[dinsdalePiranha]

Hi Gary_C, 

Thanks for responding.   Yes, they all worked fine as a mesh within the house.  Even though I'd tested the 50m CAT6 cable with a laptop, in desperation also I tried connecting the disc locally to the router using a different (1m) cable - it worked.   You live and learn.    Now to figure out what's wrong with this damn cable!

Thanks...

[Gary_C]

It shouldn't be the length but what speed did the laptop connect at ? Was it a pre-made cable ? is it copper or aluminium ?

Solid copper cat6 should be fine for 1g connection