Switch causing network issues. Assistance required please.

BurningHorizons · 15 Mar 2021 at 11:00

Hi. I've recently installed a Nova MW6 mesh wifi system at home that is working perfectly, however I wish to use its Ethernet backhaul capabilities. I've hooked up the MW6 satellite nodes to a managed Netgear GS110TP v2, however when I do this, it causes the whole network to stop working - both MW6 wireless and other wired connections cease. Through lots of trial and error I thought the MW6's might be to blame, and I was on the verge of sending them back, however I swapped out the switch for a simple Netgear unmanaged switch and the network stays up and the MW6's work perfectly with backhaul enabled. I tried another simple TP-Link switch and that works just fine too. Now I don't use the managed capabilities of GS110TP but I do need its PoE capabilities, so I can't just use one of the other simple switches in its place unfortunately. Can you think of what could be causing the GS110TP to go awry? Could there be a setting (and there are many!) that I need to change? Any assistance appreciated. TIA.

ChrisD. · 15 Mar 2021 at 11:02

Sounds like a spanning tree loop to me, can you look at the web UI of the managed switch and see if you can enable RSTP or even raise the priority as it might be taking over as the root bridge.

BurningHorizons · 15 Mar 2021 at 11:18

Thanks Chris. I can see that Spanning Tree State option is currently disabled, with STP, RSTP and MSTP as option. I'll have a play around with the settings this evening - as my wife is currently working I don't want to bring the network down! I'll report back later. Cheers.

Caged · 15 Mar 2021 at 13:02

At a guess STP being disabled means the BPDU frames are being dropped by the switch, whereas an unmanaged switch doesn't have any insight into what they are so just switches them like any other frame, and the Tenda setup can't work out its topology as a result.

Enable RSTP and leave it on the defaults, that should be all that's needed.

BurningHorizons · 15 Mar 2021 at 13:49

Mrs popped out for lunch and I'm now working with the GS110TP thanks to both of you. I enabled Spanning Tree State and RSTP in global settings and then individually enabled it on the two ports that the MW6's are connected to. I left everything else at default. No issues so far. Thank you.

neil_g · 15 Mar 2021 at 13:59

Seen that before where both WiFi and ethernet backhaul were enabled at the same time.

Not sure that explains why it worked ok on the unmanaged switch though.

WJA96 · 16 Mar 2021 at 06:19

neil_g said:
Seen that before where both WiFi and ethernet backhaul were enabled at the same time.

Not sure that explains why it worked ok on the unmanaged switch though.

It probably wasn’t really, just that the packet storm never escalated to a point where it jammed up the network to the point where it went down. On the switch with STP it saw the packet storm coming and shut down.