pfSense

Hello,

I have multiple vlans between an TrueNAS-core system and pfSense. IPV6 does not work, due to a failing Neighbor Solicitation procedure. Despite that I verdict TrueNAS-core (FreeBSD) most, I am not sure any more, since I also tested with TrueNAS-scale (Debian), having exactly the same problem.

What happens is that:
- TrueNAS (core or scale) sends a Solicitation which is NOT answered by pfSence. Consequence TrueNas does not know how to reach pfSence => No IPV6 :(
Note that in case pfSense issues a solicitation towards TrueNas, TrueNAS answers the message and the communication starts.

As far as my knowledge goes, the procedure uses four messages
RS — Router Solicitation (ICMPv6 type 133
RA — Router Advertisement (ICMPv6 type 134)
NS — Neighbor Solicitation (ICMPv6 type 135)
NA — Neighbor Advertisement (ICMPv6 type 136)

In the problem situation I only see one of then ICMPv6 type 135 send by TrueNAS. So I still verdict TrueNAS more than pfSense, however I have not enough knowledge to be sure.

Attached the IMCP-frame as send by TrueNAS

Please have a look to be sure that the problem is not related to pfSense