IPv6 Prefix delegation issues

[obi]

Hi,

End of last year I tried to configure IPv6 in my local network, however because of some lack of knowledge I was having some DNS resolution performance issues and disabled everything.

After upgrading to the latest OPNsense version (24.1_1), I wanted to give another try to that subject. However, I am now facing a weird behaviour with the prefix delegation.
I configured the WAN interface as follows:
* IPv6 Configuration Type: DHCPv6
* Prefix delegation size: 56
* Send IPv6 prefix hint: true

In the past this was fine to get a /56 prefix, however now I can only manage to get a /64 !
To confirm this is not related to my ISP, I tried with my Asus Merlin RT-AX86U wifi router. I had no problem to directly get a /56 prefix from my ISP.

Also, when trying few configuration changes, it completely stop working and I end up with the following in the logs

Code Select Expand

/usr/local/etc/rc.newwanipv6: Failed to detect IP for interface wan

Am I the only one having that issue?
How can I investigate the problem?

Thanks for the help