I tried to wake up the computer on the LAN from the WAN using WOL, but I was in trouble. After inserting and unplugging the lan cable, the arp table created by
ip neigh change * lladdr * nud permanent dev br-lan seems to be invalid.
I found a script that seems to handle this problem, but this script doesn't seem to work on my router (MT7620).
I created test scripts in the /etc/hotplug.d/net/ and /etc/hotplug.d/iface/ directories, but it seems that plugging in the lan network cable does not trigger these two hot plug events.
I don't know if this is a fault.
This is the script: