Hi! At last, it works. The error was one of the long cable that was not working if put between 2 managed switches, but as soon as there was the unmanaged switch this was working. Somehow the managed...

And yes I did the upgrade to V3 firmware. It did not help.

Ok I made a new finding. Until now I thought it was impossible to chain two managed switches but if I replace the “basement” switch by the unmanaged, I was able to chain two managed switches and at...

Thanks for the follow-up, and explaination. I did triple check that all 3 switches have the same VLAN configuration. We can simplify to a 2 switches configuration more in details if that helps. The...

I did “enable 802.1Q VLANs and leave the port settings at default” it did not work.

Hi, thanks. Not Chaining is not possible. IP adresses are well configured. I know about the 2 steps. I cannot disable all Vlans apparently, do you suggest I can? Do you know how? thanks for the...