I set up UPnP daemon on my OpenWRT box, but it shows no activity however from the logs I could see it have done something for IPv6 addresses.
Quick scan over on github would suggest this has been a long-standing omission from the Luci upnp 'app' (since 2019 at least). I can only guess that no-one has thought it important enough to spend time adding the required functionality.
Pardon my ignorance but why should upnp be necessary for IPv6?
If you want to use p2p applications like DHT you can just add the default or staticly configured ports to the firewall. (Maybe there are applications which just don't behave well that's why I'm asking....)
My ipv6 address is always changing
So is mine.
# Allow DHT and BitTorrent
## For admin
config rule
option name Allow-aria2c
option src wan
option dest admin
option family IPv6
option dest_port 6881-6999
option target ACCEPT
## For user
config rule
option name Allow-aria2c
option src wan
option dest user
option family IPv6
option dest_port 6881-6999
option target ACCEPT
# Allow Transmission; AFAICS you have to configure the "default" port on the client manually.
option rule
option name Allow-Transmission
option src wan
option dest admin
option family IPv6
option dest_port 51413
option target ACCEPT
That seems good! admin and user are hostnames of the PCs?
No, names of firewall zones.
I'm not sure just opening ports to any (and all) IPv6 hosts within a firewall zone is best practice.
miniupnpd supports “IPv6 Pinholes”.
This allows devices to request a firewall port allow rule to the device to be created.
It is the equivalent of ipv4 UPnP without the whole NAT thing.
I don’t really deal with luci so I can’t comment how the change would be made, but the firewall commands to list the opened ports is trivial.