Find bellow a summary of how to settup a DMZ with two prefixs delegations. One for the LAN and the second for the DMZ.
This setup is mainly based on guide-to-set-up-dmz-via-luci 1
First step : create a new VLAN
Open Network -> Switch to setup a VLAN. To understand your default configuration, find the Switch Ports (for VLANs) section for your router in Table of Hardware. I created an VLAN with id 24, on LAN4 ans link to CPU (eth0).
This action will create an interface named eth0.24
Second step : create a new Interface
Open Network -> Interfaces to setup the DMZ. The main setting is to set IPv6 assignement length to disabled
Third step : settup firewall rule for DMZ
Open Network -> Firewall.
This allow the LAN to get onto DMZ and prohibit DMZ to get onto LAN.
