IPv6 with Sonic ONT

[daverand]

And yes, that resolved it - thank you very much!

[brandonc]

And yes, that resolved it - thank you very much!

Of course! Thank you for bringing that to our attention. I'm glad we could fix it quickly and resolve the issue.

Kind regards,

[fourmica]

EDIT:

If anyone has this problem, the issue for me was this.

I changed ISPs from AT&T to Sonic, and for reasons I could not determine, the old IPv6 addresses from AT&T would not go away. I could delete them manually using netsh in Windows, and they popped right back up every time.

Apparently, my wifi access point (which does NOT handle routing or DHCP) was desperately caching this information and providing it... to every device on my network. I unplugged the power to the AP, waited a few minutes, and now all the old addresses are gone.

ORIGINAL POST:

I am attempting to use OPNsense 24.7 with Sonic 10G service. IPv6 works fine with the Eero device, but it doesn't suit my network. I am connecting the OPNsense WAN interface directly to the ONT.

I am set for a /56 prefix with my LAN adapter set to Track Interface, and I get 2001 IPv6 addresses on my devices. But all traffic is being blocked by the firewall. I haven't created any new rules for the firewall rule stack, or changed anything from the default.

I recognize this is more of an OPNsense problem than a Sonic problem, but I'm hoping someone here has had similar issues.

[marcmeszaros]

I have OPNsense 25.1 and am also trying to get IPv6 working.

When I connect a Macbook Pro to the ONT I got a /128 and it worked. When I setup DHCPv6 I get a /56 IA_PD and I correctly setup interface tracking (the /64 were delegated to the LAN interface with 2001:... addresses).

I added some firewall rules to allow all IPv6 through. I briefly got it working after a bunch of CLI commands on the OPNsense device and https://ipv6-test.com/ confirmed the IPv6 address.

The strange thing is I got some IA_NA failures in the logs briefly.

<187>1 2025-05-29T01:48:06-07:00 opnsense.example.xyz dhcpd 14047 - [meta sequenceId="53"] No pool found for IA_NA address 2001:5a8:*:*::2000
<187>1 2025-05-29T01:48:06-07:00 opnsense.example.xyz dhcpd 14047 - [meta sequenceId="54"] No pool found for IA_NA address 2001:5a8:*:*::16d5
<190>1 2025-05-29T01:48:06-07:00 opnsense.example.xyz dhcpd 14047 - [meta sequenceId="55"] Wrote 0 NA, 0 TA, 0 PD leases to lease file.
<190>1 2025-05-29T01:48:06-07:00 opnsense.example.xyz dhcpd 14047 - [meta sequenceId="56"] Bound to *:547
<190>1 2025-05-29T01:48:06-07:00 opnsense.example.xyz dhcpd 14047 - [meta sequenceId="57"] Listening on Socket/8/igb1/2001:5a8:*:*::/64
<190>1 2025-05-29T01:48:06-07:00 opnsense.example.xyz dhcpd 14047 - [meta sequenceId="58"] Sending on Socket/8/igb1/2001:5a8:*:*::/64

To be fair, I was doing a bunch of commands to clear cache and get router advertisements in quick succession.

I'm always able to ping the upstream IPv6 gateway router, but can never seem to ping other public IPv6 addresses.

Does anyone have a working example of an OPNsense configuration actually working?

[skyweir]

While I no longer employ OPNSense on my network I found this site which was extremely helpful with the initial config. Using his suggestions everything just worked.

https://homenetworkguy.com/how-to/begin ... -opnsense/

[marcmeszaros]

EDIT: Seems like it was only temporary, after a reboot/release seems like it doesn't work again.

Not sure what in my config was broken, but I did a factory reset and it seems to work now.