You have already created a trunk interface by tagging vlan 10 and vlan 20 traffic on your tplink switch port 1. If your firewall expects all traffic coming from the tplink to be tagged respectively...

I would also like to see this changed. I have the TL-SG1016DE and you can access the management interface of the switch on any VLAN either with the Smart utility or by assigning the PC you are at an...