ThiefMaster:

Same report as in the GitHub issue I created, just opening one here as well in case this tracker is preferred:
openwrt/odhcpd#121

Since updating to the latest OpenWRT a few weeks ago, I noticed that my Axis IP cameras do not get a stateful IPv6 anymore, which worked fine before.

Since they receive NOTONLINK responses, I have the feeling that the issue got introduced with commit a2ffc5986cd35bea983b81b28b8a656e3b81fdf1. Might be a shitty dhcpv6 implementation on the camera, I don't know and I'm not familiar enough with DHCPv6 to see a bad implementation just from looking at the code.

The code of the "mdhcp6" client the camera uses is available in this git repo. Not sure if it's 100% up to date though, but I can reproduce the issue reliably.

Here's a pcap on my older router running LEDE 17.01.3: mdhcp6-lede-17.01.3.pcap.gz
The advertise/request messages don't contain anything related to the configured IP (via the 'hostid' option), but the final reply contains the correct IP.

And here's a pcap on another router running the latest OpenWRT 18.06.1, coming from the exact same mdhcp6 client (just running on a different machine since they are different networks, hence the different DUID): mdhcp6-openwrt-18.06.1.pcap.gz

I'm not sure where the problem is - in the server or the client (more likely, since all other dhcpv6 clients work perfectly fine). But I'd appreciate some help - if it's a bug in the client (not sending any IA_NA requests in the solicit seems strange to me), I'd like to forward details to the camera vendor. They release firmware updates quite often so I think the chance that they actually fix their dhcpv6 client if it's broken is quite high.