Messages

After reviewing everything and doing more tests with the gateways and routes, nothing. Here's an example of a traceroute from a client to google.com:

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traceroute to google.com (2a00:1450:4001:82f::200e), 5 hops max, 80 byte packets
1  firewall.lan (2003:c9:7f3d:4202:2e0:67ff:fe21:15e0)  0.254 ms  0.189 ms  0.215 ms
2  * * *
3  * * *
4  * * *
5  * * *


Here's from the firewall (it eventually reaches the destination)

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traceroute6 to google.com (2a00:1450:4001:800::200e) from 2003:c9:7f3d:4202:2e0:67ff:fe21:15e0, 18 hops max, 20 byte packets
1  2003:0:8a01:3800::1  5.464 ms  3.911 ms  4.087 ms
2  2003:0:1807::1  10.928 ms  11.276 ms  11.136 ms
3  2001:4860:1:1:0:cf8:0:22  10.453 ms  10.826 ms  10.484 ms
4  2a00:1450:8019::1  9.749 ms  9.937 ms  9.786 ms
5  2001:4860:0:1::3e8a  12.026 ms  12.434 ms  11.608 ms
...

I'm at loss. Also, I've checked the logs, and that started to happen when I upgraded to 22.1, so I doubt is a coincidence. I've captured some traffic while doing pings, but with the ipv6 thing, I'm not really sure what do I have to look for.

Any help, besides reinstalling and starting from scratch?

Hello everybody,

IPv6 from the local network to the internet suddenly stopped working. I'm not sure exactly when, but probably when I updated to 22.1 some days ago. In the local network, it works as expected.

What works:

- WAN gets an IPv6 address and a prefix
- All the clients of the VLANs get a proper IPv6 address within the subprefix (actually more than one)
- All the clients get an ULA, which I configured using virtual IPs and router advertisements (and that worked before)
- Clients can communicate between each other using IPv6, both with ULAs and GUAs, respecting the firewall rules

What doesn't work:

- Clients cannot communicate with the internet with IPv6, e.g. pinging google.com fails, no message, just 100% packet loss
- However, I can IPv6 ping from the firewall to the outside and it works: Interfaces -> Diagnostics -> Ping, pinging to google.com with MAIN as the source address (that's the main VLAN, where computer, phones, etc are) works
- Running e.g. https://ipv6-test.com/ from any client says there is no IPv6 connectivity

What I've tried:

- Deactivating firewall rules
- Deactivating virtual IPs and ULAs
- Deactivating manual router advertisements
- Changing types of RA (assisted, managed, stateless, etc)
- Restarting multiple times

I suspect opnsense is failing to route properly. I captured the packages in both MAIN and WAN interfaces while trying to ping from my computer to google.com. The pings packets appear in both captures, and it says: [Expert Info (Warning/Sequence): No response seen to ICMPv6 request in frame 3]

Gateways and routes are with the default values.

Thanks for the help.

Another problem I have and I haven't seen in the forum:

I'm trying to update both ipv4 and ipv6 with cloudflare. It only updates one of them, depending on the "Check IP method" I choose. It seems that we should be able to choose more than one method, or even better, read the IP locally.

You can use IPv4 internally, but that is pretty much the same as using ULA internally. The ULA you would configure the same as the internal IPv4, only as a virtual IP on the internal interface.

Well, it's not the same. As I explained, I can use ULAs with virtual IPs, but I cannot configure them with DHCPv6 because they aren't the "main"  address and it shows an "valid range" error. And it doesn't work with slaac anyway.

Not sure if you are aware but to configure DHCPv6 and radvd parameters you need to check "Manual configuration" in the interface.

I am aware of that, I couldn't have tried to use DHCPv6 if I weren't .

I have a local network with a bunch of hosts composed of linux, windows and android clients. I'm trying to have ipv6 working locally with DNS resolution. i.e., I want to be able to e.g. go to local-computer.local-domain.com, and have the DNS server resolve its IPv6 address, and access using it. Because of android, I am forced to use, or at least support, SLAAC.

My current setup:

• OPNsense
• Unbound - I am open to use any other DNS server if that solves the problem
• I have a /56 IPv6 DYNAMIC prefix from my ISP, no possibility to make it static (also, I don't want to change everything if I change ISP)
• Multiple VLANs, with ipv6 configured via tracking interface
• I have static ipv4 addresses for most hosts of my network via DHCPv4, which also assigns a hostname, correctly and automatically registered in unbound

What works:

• DNS IPv4 resolution in the local network
• Every host have (at least one) an ipv6 address
• Hosts can use ipv6 locally: they can ping, ssh, whatever
• Hosts can access the internet with ipv6: when going to google.com it resolves to the ipv6 address and it works

What doesn't work:

• Hosts accessing the local network with hostnames and ipv6

What I have tried:

• After reading a lot , I think that one solution is to set ULA for the VLANS.
• I have set virtual IPs with an ULA for each VLAN, in fd::. It works, meaning that the hosts get at least one ULA address. However, I don't know what to do with it. Honestly I haven't tried to set up firewall rules with them, but if I set them using them, would it work, considering they also have more addresses? I mean, if I put a rule that says "hosts with address fdULA:address:of:IOT:VLAN" cannot comunicate with "hosts with address fdULA:address:of:IOT:MANAGEMENT", wouldn't they be able to send things to MANAGEMENT since they have other addresses not related to ULA?
• In any case, despite having ULA addresses, I don't know what to do with it, or how it solves my problem. I cannot set static ULA addresses in DHCPv6 because they are "virtual" addresses, and it complains about "A valid range must be specified."
• I think I would have the same DNS problem as before, the addresses won't be registered in the DNS server.

What I'm trying:

• Apparently mdns is an important thing with IPv6. However, I would like to keep using a normal DNS server, because I might have things (usually IoT things) that don't understand mdns. What I thought was to let the mdns devices send their multicast, and have the DNS server get them and register them, so it will answer to normal DNS requests. However it seems that that's quite a weird thing to do and it's not supported anywhere, so if I go with that route, I would have to do a script or something.
• I have found this thing that looks it could help: http://www.dns-sd.org/ , but I have no idea what to do with it, or how to implement it.

Other possibilities:

• Use only ULA for the internal network, and use NPT for translating it to the external prefix. However, AFAIK OPNsense doesn't support dynamic prefixes in NPT, making it useless.
• Use IPv4 internally, but allow hosts to have IPv6 addresses for communicating with the exterior. The more I try things, and the more I learn about IPv6, the more I like this solution. I don't see how can I implement it, though, it looks that is either IPv6 for everything, or for nothing. I would have to force the DNS server to give only IPv4 addresses internally, or something.

I'm a bit surprised that I haven't found anything on the internet about this, it seems like a quite basic thing to do. Here are some links I've read and haven't helped. I have read way more things, but I cannot find them right now:
https://www.reddit.com/r/OPNsenseFirewall/comments/gnsa1t/multiple_ipv6_prefixes_per_interface/
https://forum.opnsense.org/index.php?topic=15529.0

Hi,

vielleicht ist schon zu spät, aber ich hatte ein ähnliches Problem, auch mit Telekom (aber VDSL), wenn meine Interfaces die IPv6 Adressen nach 4 Stunden verloren. Ich denke, dass mein Problem ganz anders war, aber vielleicht fixet es das auch für dich:

https://forum.opnsense.org/index.php?topic=20969.0

So I finally solved this before testing the rc version. After trying to do some IPv6 Link-Local pings between interfaces and failing, I came across this post: https://forum.opnsense.org/index.php?topic=17407.30

Activating the option "Disable force gateway" in the advance settings of the firewall solved it. Now there's no more "transmit failed: No route to host" in the dhcp6c log, and the IPv6 prefix is being renewed every 15 minutes. The IPv6 addresses in the VLANs are still there, and I'm still using the same prefix.

I have a couple of questions, however: I haven't seen this setting in any of the guides I have seen about connecting to Deutsche Telekom. It also worked for me until about 30th October, when I first found about this. I wonder if this option is patching some misconfiguration on my part, and I shouldn't need it.

I also wonder where would be the logs for this anywhere. As I mentioned, the gateway log was empty. I was expecting something like "XXX tried to send YYY to ZZZ" somwhere for easing debugging. Is there an option for this? I guess it should be in gateways or routes or something.

How stable is 21.1? I was thinking on using the development version to see if it breaks something, but I thought I rather not, since I think it should be released soon enough. Could you point me to the commit of that fix, to see what's what?

Thanks marjohn56 for the answer.

That's what I thought, something was blocking some ICMP-IPV6 thing, but the firewall logs don't show anything (I'm logging almost everything right now, at least the blocking and rejecting rules). And if that is the case, I don't know why it works at the beginning of a pppoe connection, where I get a prefix, address and everything. But it makes sense that both things are related.

I attach a picture of the gateways (I took the screenshot right now, when the IPv6 is working). I didn't do anything here, so I assume they are the default ones. The gateway logs are empty, I don't know how to populate them with something.

Hi all,

Since some time (I cannot exactly pinpoint when, but at least a couple of months), I have this problem where the local nets loss IPv6 connectivity after exactly 4 hours. It is restored after reconfiguring the WAN interface (or reconnecting in Interfaces -> Overview). Restarting radvd doesn't do anything. The WAN interface still has a working IPv6 address, however.

When this happens, the service dhcpd6 is down and cannot be (re)started. If I try to start it from the console, I get the following:

/usr/local/etc/rc.d/dhcp6c: WARNING: /usr/local/etc/dhcp6c.conf is not readable.

that file doesn't exist, btw.

My setup:

ISP: Telekom in Germany, known for not providing static IPv6 addreses or prefixes.

WAN Interface, connecting using PPPoE and a Draytek Vigor 165 modem in bridge mode:
Request only an IPv6 prefix: true
Prefix delegation size: 56
Send IPv6 prefix hint: true
Use IPv4 connectivity: true
Prevent release: true

Local interfaces: A bunch of VLANs, all of them tracking the WAN interface with different prefixes.

DHCPv6, router advertisments, etc. are all running with the default values.

I'm currently running radvd 2.19 because I thought it may be related to the famous bug https://github.com/opnsense/core/issues/4338, but no luck. I also ran the rtadvd patch of the same bug, with same result. I can attach the full system, routing and dhcp logs for a period of ~4 hours between a restart of the interface and the loss of IPv6 if needed, for now I'll post the things I think are relevant (max debug settings), when IPv6 is lost

system:

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2021-01-17T21:29:38 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=9, retrans=115332
2021-01-17T21:29:38 dhcp6c[83558] transmit failed: No route to host
2021-01-17T21:29:38 dhcp6c[83558] set IA_PD
2021-01-17T21:29:38 dhcp6c[83558] set IA_PD prefix
2021-01-17T21:29:38 dhcp6c[83558] set option request (len 4)
2021-01-17T21:29:38 dhcp6c[83558] set elapsed time (len 2)
2021-01-17T21:29:38 dhcp6c[83558] set identity association
2021-01-17T21:29:38 dhcp6c[83558] set client ID (len 14)
2021-01-17T21:29:12 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=129, retrans=127656
2021-01-17T21:29:12 dhcp6c[83558] transmit failed: No route to host
2021-01-17T21:29:12 dhcp6c[83558] set option request (len 4)
2021-01-17T21:29:12 dhcp6c[83558] set elapsed time (len 2)
2021-01-17T21:29:12 dhcp6c[83558] set identity association
2021-01-17T21:29:12 dhcp6c[83558] set client ID (len 14)
2021-01-17T21:27:26 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=8, retrans=131892
2021-01-17T21:27:26 dhcp6c[83558] transmit failed: No route to host
2021-01-17T21:27:26 dhcp6c[83558] set IA_PD
2021-01-17T21:27:26 dhcp6c[83558] set IA_PD prefix
2021-01-17T21:27:26 dhcp6c[83558] set option request (len 4)
2021-01-17T21:27:26 dhcp6c[83558] set elapsed time (len 2)
2021-01-17T21:27:26 dhcp6c[83558] set identity association
2021-01-17T21:27:26 dhcp6c[83558] set client ID (len 14)
2021-01-17T21:27:18 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=128, retrans=113724
2021-01-17T21:27:18 dhcp6c[83558] transmit failed: No route to host
2021-01-17T21:27:18 dhcp6c[83558] set option request (len 4)
2021-01-17T21:27:18 dhcp6c[83558] set elapsed time (len 2)
2021-01-17T21:27:18 dhcp6c[83558] set identity association
2021-01-17T21:27:18 dhcp6c[83558] set client ID (len 14)
2021-01-17T21:25:28 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=7, retrans=118056
2021-01-17T21:25:28 dhcp6c[83558] transmit failed: No route to host
2021-01-17T21:25:28 dhcp6c[83558] set IA_PD
2021-01-17T21:25:28 dhcp6c[83558] set IA_PD prefix
2021-01-17T21:25:28 dhcp6c[83558] set option request (len 4)
2021-01-17T21:25:28 dhcp6c[83558] set elapsed time (len 2)
2021-01-17T21:25:28 dhcp6c[83558] set identity association
2021-01-17T21:25:28 dhcp6c[83558] set client ID (len 14)
2021-01-17T21:25:14 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=127, retrans=124500
2021-01-17T21:25:14 dhcp6c[83558] transmit failed: No route to host
2021-01-17T21:25:14 dhcp6c[83558] set option request (len 4)
2021-01-17T21:25:14 dhcp6c[83558] set elapsed time (len 2)
2021-01-17T21:25:14 dhcp6c[83558] set identity association
2021-01-17T21:25:14 dhcp6c[83558] set client ID (len 14)
2021-01-17T21:24:38 dhcp6c[83558] removing an event on pppoe0, state=REBIND
2021-01-17T21:24:28 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=6, retrans=60193
2021-01-17T21:24:28 dhcp6c[83558] transmit failed: No route to host
2021-01-17T21:24:28 dhcp6c[83558] set IA_PD
2021-01-17T21:24:28 dhcp6c[83558] set IA_PD prefix
2021-01-17T21:24:28 dhcp6c[83558] set option request (len 4)
2021-01-17T21:24:28 dhcp6c[83558] set elapsed time (len 2)
2021-01-17T21:24:28 dhcp6c[83558] set identity association
2021-01-17T21:24:28 dhcp6c[83558] set client ID (len 14)
2021-01-17T21:23:57 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=5, retrans=30329
2021-01-17T21:23:57 dhcp6c[83558] transmit failed: No route to host
2021-01-17T21:23:57 dhcp6c[83558] set IA_PD
2021-01-17T21:23:57 dhcp6c[83558] set IA_PD prefix
2021-01-17T21:23:57 dhcp6c[83558] set option request (len 4)
2021-01-17T21:23:57 dhcp6c[83558] set elapsed time (len 2)
2021-01-17T21:23:57 dhcp6c[83558] set identity association
2021-01-17T21:23:57 dhcp6c[83558] set client ID (len 14)
2021-01-17T21:23:42 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=4, retrans=15552
2021-01-17T21:23:42 dhcp6c[83558] transmit failed: No route to host
2021-01-17T21:23:42 dhcp6c[83558] set IA_PD
2021-01-17T21:23:42 dhcp6c[83558] set IA_PD prefix
2021-01-17T21:23:42 dhcp6c[83558] set option request (len 4)
2021-01-17T21:23:42 dhcp6c[83558] set elapsed time (len 2)
2021-01-17T21:23:42 dhcp6c[83558] set identity association
2021-01-17T21:23:42 dhcp6c[83558] set client ID (len 14)
2021-01-17T21:23:34 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=3, retrans=7950
2021-01-17T21:23:34 dhcp6c[83558] transmit failed: No route to host
2021-01-17T21:23:34 dhcp6c[83558] set IA_PD
2021-01-17T21:23:34 dhcp6c[83558] set IA_PD prefix
2021-01-17T21:23:34 dhcp6c[83558] set option request (len 4)
2021-01-17T21:23:34 dhcp6c[83558] set elapsed time (len 2)
2021-01-17T21:23:34 dhcp6c[83558] set identity association
2021-01-17T21:23:34 dhcp6c[83558] set client ID (len 14)
2021-01-17T21:23:30 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=2, retrans=4145
2021-01-17T21:23:30 dhcp6c[83558] transmit failed: No route to host
2021-01-17T21:23:30 dhcp6c[83558] set IA_PD
2021-01-17T21:23:30 dhcp6c[83558] set IA_PD prefix
2021-01-17T21:23:30 dhcp6c[83558] set option request (len 4)
2021-01-17T21:23:30 dhcp6c[83558] set elapsed time (len 2)
2021-01-17T21:23:30 dhcp6c[83558] set identity association
2021-01-17T21:23:30 dhcp6c[83558] set client ID (len 14)
2021-01-17T21:23:27 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=1, retrans=2116
2021-01-17T21:23:27 dhcp6c[83558] transmit failed: No route to host
2021-01-17T21:23:27 dhcp6c[83558] set IA_PD
2021-01-17T21:23:27 dhcp6c[83558] set IA_PD prefix
2021-01-17T21:23:27 dhcp6c[83558] set option request (len 4)
2021-01-17T21:23:27 dhcp6c[83558] set elapsed time (len 2)
2021-01-17T21:23:27 dhcp6c[83558] set identity association
2021-01-17T21:23:27 dhcp6c[83558] set client ID (len 14)
2021-01-17T21:23:26 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=0, retrans=1046
2021-01-17T21:23:26 dhcp6c[83558] transmit failed: No route to host
2021-01-17T21:23:26 dhcp6c[83558] set IA_PD
2021-01-17T21:23:26 dhcp6c[83558] set IA_PD prefix
2021-01-17T21:23:26 dhcp6c[83558] set option request (len 4)
2021-01-17T21:23:26 dhcp6c[83558] set elapsed time (len 2)
2021-01-17T21:23:26 dhcp6c[83558] set identity association
2021-01-17T21:23:26 dhcp6c[83558] set client ID (len 14)
2021-01-17T21:23:26 dhcp6c[83558] a new XID (c66c0e) is generated
2021-01-17T21:23:26 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=126, retrans=108036
2021-01-17T21:23:26 dhcp6c[83558] transmit failed: No route to host
2021-01-17T21:23:26 dhcp6c[83558] set option request (len 4)
2021-01-17T21:23:26 dhcp6c[83558] set elapsed time (len 2)
2021-01-17T21:23:26 dhcp6c[83558] set identity association
2021-01-17T21:23:26 dhcp6c[83558] set client ID (len 14)
2021-01-17T21:23:26 dhcp6c[83558] remove a site prefix 2003:f6:1720:b300::/56
2021-01-17T21:23:26 dhcp6c[83558] prefix timeout for 2003:f6:1720:b300::/56
2021-01-17T21:21:27 dhcp6c[83558] reset a timer on pppoe0, state=SOLICIT, timeo=125, retrans=118908

routing:

Code Select Expand


2021-01-17T21:27:04 radvd[81185] processed RA on igb1_vlan20
2021-01-17T21:27:04 radvd[81185] igb1_vlan20 received RA from: fe80::2e0:67ff:fe21:15e0 (myself)
2021-01-17T21:27:04 radvd[81185] igb1_vlan20 received a packet
2021-01-17T21:27:04 radvd[81185] igb1_vlan20 recvmsg len=104
2021-01-17T21:27:04 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:27:04 rtsold[10889] <rtsol_input> received RA from fe80::2e0:67ff:fe21:15e0 on an unexpected IF(igb1_vlan20)
2021-01-17T21:27:04 radvd[81185] polling for 43.857 second(s), next iface is igb1_vlan128
2021-01-17T21:27:04 radvd[81185] igb1_vlan20 processed an RS
2021-01-17T21:27:04 radvd[81185] igb1_vlan20 next scheduled RA in 447.997 second(s)
2021-01-17T21:27:04 radvd[81185] sending RA to ff02::1 on igb1_vlan20 (fe80::2e0:67ff:fe21:15e0), 5 options (using 104/1224 bytes)
2021-01-17T21:27:04 radvd[81185] checking ipv6 forwarding not supported
2021-01-17T21:27:04 radvd[81185] igb1_vlan20 is ready
2021-01-17T21:27:04 radvd[81185] igb1_vlan20 address: fe80::2e0:67ff:fe21:15e0
2021-01-17T21:27:04 radvd[81185] igb1_vlan20 linklocal address: fe80::2e0:67ff:fe21:15e0
2021-01-17T21:27:04 radvd[81185] checking ipv6 forwarding of interface not supported
2021-01-17T21:27:04 radvd[81185] prefix length for igb1_vlan20 is -1
2021-01-17T21:27:04 radvd[81185] link layer token length for igb1_vlan20 is 48
2021-01-17T21:27:04 radvd[81185] mtu for igb1_vlan20 is 1500
2021-01-17T21:27:04 radvd[81185] igb1_vlan20 supports multicast or is point-to-point
2021-01-17T21:27:04 radvd[81185] igb1_vlan20 is running
2021-01-17T21:27:04 radvd[81185] igb1_vlan20 is up
2021-01-17T21:27:04 radvd[81185] ioctl(SIOCGIFFLAGS) succeeded on igb1_vlan20
2021-01-17T21:27:04 radvd[81185] igb1_vlan20 received RS from: ::
2021-01-17T21:27:04 radvd[81185] igb1_vlan20 received a packet
2021-01-17T21:27:04 radvd[81185] igb1_vlan20 recvmsg len=8
2021-01-17T21:27:02 radvd[81185] polling for 19.184 second(s), next iface is igb1_vlan20
2021-01-17T21:27:02 radvd[81185] igb0 received icmpv6 RS/RA packet on an unknown interface with index 1
2021-01-17T21:27:02 radvd[81185] igb0 received a packet
2021-01-17T21:27:02 radvd[81185] igb0 recvmsg len=104
2021-01-17T21:27:02 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:27:02 rtsold[10889] <rtsol_input> received RA from fe80::2e0:67ff:fe21:15e0 on an unexpected IF(igb0)
2021-01-17T21:27:02 radvd[81185] polling for 19.184 second(s), next iface is igb1_vlan20
2021-01-17T21:27:02 radvd[81185] processed RA on igb1
2021-01-17T21:27:02 radvd[81185] igb1 received RA from: fe80::2e0:67ff:fe21:15e0 (myself)
2021-01-17T21:27:02 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:27:02 radvd[81185] igb1 received a packet
2021-01-17T21:27:02 rtsold[10889] <rtsol_input> received RA from fe80::2e0:67ff:fe21:15e0 on an unexpected IF(igb1)
2021-01-17T21:27:02 radvd[81185] igb1 recvmsg len=104
2021-01-17T21:27:02 radvd[81185] polling for 19.184 second(s), next iface is igb1_vlan20
2021-01-17T21:27:02 radvd[81185] igb1 next scheduled RA in 545.178 second(s)
2021-01-17T21:27:02 radvd[81185] sending RA to ff02::1 on igb1 (fe80::2e0:67ff:fe21:15e0), 5 options (using 104/1210 bytes)
2021-01-17T21:27:02 radvd[81185] checking ipv6 forwarding not supported
2021-01-17T21:27:02 radvd[81185] igb1 is ready
2021-01-17T21:27:02 radvd[81185] igb1 address: fe80::2e0:67ff:fe21:15e0
2021-01-17T21:27:02 radvd[81185] igb1 linklocal address: fe80::2e0:67ff:fe21:15e0
2021-01-17T21:27:02 radvd[81185] checking ipv6 forwarding of interface not supported
2021-01-17T21:27:02 radvd[81185] prefix length for igb1 is 64
2021-01-17T21:27:02 radvd[81185] link layer token length for igb1 is 48
2021-01-17T21:27:02 radvd[81185] mtu for igb1 is 1500
2021-01-17T21:27:02 radvd[81185] igb1 supports multicast or is point-to-point
2021-01-17T21:27:02 radvd[81185] igb1 is running
2021-01-17T21:27:02 radvd[81185] igb1 is up
2021-01-17T21:27:02 radvd[81185] ioctl(SIOCGIFFLAGS) succeeded on igb1
2021-01-17T21:27:02 radvd[81185] timer_handler called for igb1
2021-01-17T21:24:55 radvd[81185] polling for 127.233 second(s), next iface is igb1
2021-01-17T21:24:55 radvd[81185] pppoe0 received icmpv6 RS/RA packet on an unknown interface with index 15
2021-01-17T21:24:55 radvd[81185] pppoe0 received a packet
2021-01-17T21:24:55 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:24:55 rtsold[10889] <rtsol_input> received RA from fe80::9ecc:83ff:fe81:ea6e on an unexpected IF(pppoe0)
2021-01-17T21:24:55 radvd[81185] pppoe0 recvmsg len=96
2021-01-17T21:23:26 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 13, len=164
2021-01-17T21:23:26 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 2, len=272
2021-01-17T21:23:26 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 2, len=344
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 13, len=164
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 2, len=272
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 2, len=344
2021-01-17T21:23:26 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:23:26 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 2, len=344
2021-01-17T21:23:26 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 13, len=164
2021-01-17T21:23:26 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 2, len=272
2021-01-17T21:23:26 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 2, len=344
2021-01-17T21:23:26 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 13, len=164
2021-01-17T21:23:26 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 2, len=272
2021-01-17T21:23:26 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 2, len=344
2021-01-17T21:23:26 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 13, len=164
2021-01-17T21:23:26 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:23:26 rtsold[10889] <rtsock_input> rtmsg type 2, len=272
2021-01-17T21:23:25 radvd[81185] polling for 217.167 second(s), next iface is igb1
2021-01-17T21:23:25 radvd[81185] processed RA on igb1_vlan20
2021-01-17T21:23:25 radvd[81185] igb1_vlan20 received RA from: fe80::2e0:67ff:fe21:15e0 (myself)
2021-01-17T21:23:25 radvd[81185] igb1_vlan20 received a packet
2021-01-17T21:23:25 radvd[81185] igb1_vlan20 recvmsg len=104
2021-01-17T21:23:25 rtsold[10889] <rtsol_check_timer> there is no timer
2021-01-17T21:23:25 rtsold[10889] <rtsol_input> received RA from fe80::2e0:67ff:fe21:15e0 on an unexpected IF(igb1_vlan20)
2021-01-17T21:23:25 radvd[81185] polling for 217.167 second(s), next iface is igb1
2021-01-17T21:23:25 radvd[81185] igb1_vlan20 processed an RS
2021-01-17T21:23:25 radvd[81185] igb1_vlan20 next scheduled RA in 236.363 second(s)
2021-01-17T21:23:25 radvd[81185] sending RA to ff02::1 on igb1_vlan20 (fe80::2e0:67ff:fe21:15e0), 5 options (using 104/1224 bytes)
2021-01-17T21:23:25 radvd[81185] checking ipv6 forwarding not supported
2021-01-17T21:23:25 radvd[81185] igb1_vlan20 is ready
2021-01-17T21:23:25 radvd[81185] igb1_vlan20 address: fe80::2e0:67ff:fe21:15e0
2021-01-17T21:23:25 radvd[81185] igb1_vlan20 address: 2003:f6:1720:b314:2e0:67ff:fe21:15e0
2021-01-17T21:23:25 radvd[81185] igb1_vlan20 linklocal address: fe80::2e0:67ff:fe21:15e0


I don't have a radvdump file, but after the error happens, it losses the lines for the prefix and RDNSS.

I also have tcpdump files for this 4 hour period of all the interfaces, I can attach them by request. Surprisingly, the capture for the pppoe interface is empty.

One thing that bothers me, that may or may not be related, are all the "dhcp6c[83558]   transmit failed: No route to host" messages that appear in the system log. They are also there when the WAN interface is reconnected and the IPv6 are running.

When I have time, I may start with a fresh opnsense installation from scratch, maybe is some wrongly configured thing somewhere, but I would like to avoid it if possible, since I'm working from home and need internet.

Thanks for the help.