Modem mode + Network Switch + Mesh

[Gnans]

Hello forum members,

I'm trying to solve an issue and hope you could help.

July 2021 - I changed my Hub 3 to be in Modem mode and use with Deco Mesh set-up. Everything works well as all devices only connect to WiFi. Something like this Coax cable-> Hub3 (Modem mode) -> Deco Mesh

Nov 2021 - I wanted to get some devices connected through LAN (for various reasons). I got a TPLink 8 port unmanaged switch and trying to connect in the architecture as below.

Coax cable-> Hub3 (Modem mode) -> Network switch -> Deco Mesh + LAN cables.

In the above set-up my Mesh still works well but the LAN cables pretends to give some internet. The lights on the devices (green and yellow) blink but none of the devices identify and connect to the network.

I have tried to remove the mesh to see if that was the problem but it did not. May be I'm not getting the basic of Router and Modem mode and would that be the cause? I can go back to router mode but wondering if there is something fundamentally wrong here.

Thanks for all your valuable response,

Gnans

[Adduxi · Accepted solution]

No.  The switch needs to be after the first Deco. So Hub - Deco - Switch - LAN 

It will not work otherwise. 

[Gnans]

Ah interesting, I will re-wire them and update the progress here. Thanks for the super quick response.

[legacy1]

I do wonder how mesh works as a router with its ports not dedicated as a WAN port that it just does a DHCP and is a switch when a PC is connected too does DHCP and is a race as to what gets the WAN IP.

[Gnans]

Solution - As marked above. This works when I swapped the Deco and N/W switch position.

Something for me to research though if the Switch will now work as a proper gigabit etc.

[Adduxi]

If it is a gigabit switch then it will work. Just make sure you are using good Cat 6 cables.