Running native ipv6 but I get no ipv6 default route

[gunnarf]

My ISP provides me with a /56 range of ipv6. My clients gets ipv6 addresses, but dhcpv6 doesn't provide a default route. It did work a while ago. I haven´t changed my config, so what can be wrong.

[Taralas]

I seem to be getting a similar, but slightly different issue. From what I can tell, my device is generating a IPv6 RA, which seems to be correctly formatted. Linux hosts are receiving it, and it seems to be correctly formed:

Code: [Select]

#
# radvd configuration generated by radvdump 2.17
# based on Router Advertisement from fe80::f690:eaff:fe00:72c0
# received by interface eth0
#

interface eth0
{
        AdvSendAdvert on;
        # Note: {Min,Max}RtrAdvInterval cannot be obtained with radvdump
        AdvManagedFlag on;
        AdvOtherConfigFlag on;
        AdvReachableTime 0;
        AdvRetransTimer 0;
        AdvCurHopLimit 64;
        AdvDefaultLifetime 1800;
        AdvHomeAgentFlag off;
        AdvDefaultPreference medium;
        AdvLinkMTU 1500;
        AdvSourceLLAddress on;

        prefix {ISP ASSIGNED BLOCK}::/64
        {
                AdvValidLifetime 86400;
                AdvPreferredLifetime 14400;
                AdvOnLink on;
                AdvAutonomous off;
                AdvRouterAddr off;
        }; # End of prefix definition


        RDNSS {DNS SERVERS IPv6 ADDRESSES}
        {
                AdvRDNSSLifetime 600;
        }; # End of RDNSS definition


        DNSSL {LOCAL SEARCH DOMAIN}
        {
                AdvDNSSLLifetime 600;
        }; # End of DNSSL definition

}; # End of interface definition
For some reason, as of about 1 day ago, the Windows machines on my network are not processing the RA and adding the OPNsense LAN interface to the IPv6 route table. If I add it manually, they are able to send and receive traffic, but this doesn't seem to work via the RA process, as it does for the Linux and BSD hosts.

[Taralas]

Quick update: this one has me scratching my head. After I did a Wireshark capture, I was able to determine that the RA was not being carried across a particular switch. Once I power cycled that switch, I was able to get the Windows machines to see the RA, and update their routes.

I am at a bit of a loss to figure out why this switch (a Netgear GS716T on 6.3.1.39 firmware) would start filtering RA...

[GiantJack]

did you check if opnsense itself find an ipv6 route?

On my side,devices on my LAN receive an IPv6 address but won't reach internet:
- traceroute from laptop to google dns (ipv6) will stop when reaching opnsense
- traceroute from opnsense itself to google ipv6 dns give "no route to host"

I didn't tried the netgear switch trick but has opnsense itself cannot find its way,
my situation is a bit different.
what about you @gunnarf ?

[dinguz]

I am at a bit of a loss to figure out why this switch (a Netgear GS716T on 6.3.1.39 firmware) would start filtering RA...

I have a similar switch (GS116Ev2) and I'm seeing the same issue. Do you happen to have igmp snooping or another form of multicast filtering enabled on the switch?

[Taralas]

I do not. I have a few Netgear switches, and checked all of them, and IGMP snooping is disabled, as well as anything related to multicast routing. For the moment, the configuration is a flat network, with no VLANS, so the need for those services is minimal.

It's bad enough that I am having to bounce the WAN interfaces and switch ports daily to get a working IPv6 route. Some devices are able to get a route via RA, all of them are receiving the announcement, but it is garbled on some devices through this switch.