No IPv6 address assigned on WAN interface / Router Advertisement ignored

[marjohn56]

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Describe the bug

IPv6 ICMPv6 RS does not get sent over a PPPoE link.

To Reproduce

Steps to reproduce the behavior:

You'll need to set up a PPPoE server! Reason being the interface needs to come up on PPPoE v4 before you can see anything. Once you have done this then using Wireshark monitor the ICMPv6 traffic being sent to the PPPoE server, there is no RS being sent.

Expected behavior
ICMPv6 RS packets should be sent over the PPPoE link

OPNsense 21.1.r_96-amd64FreeBSD 12.1-RELEASE-p12-
HBSDOpenSSL 1.1.1i 8 Dec 2020
Intel(R) Core(TM) i5-5250U CPU @ 1.60GHz (4 cores)

Solution is to not use the -a flag on RTSOLD as that prohibits RS being sent on point to point interfaces ( according to the man ), but to supply the actual interfaces on the command instead.

[fichtner]

opnsense/src@2485dc0351

[fichtner]

For the record, the PPP limitation came from KAME in 2000 to FreeBSD via freebsd/freebsd-src@804c83d4bd3 with the "-a" option. Since we force PPPoE interfaces one way or another and the auto-probe just adds devices to the argument list like we would pass it we are good here. Thanks for the pointers to the problem.