1
23.7 Legacy Series / Re: OSPFv3 broken - MLDv2 announcements not being sent
« on: December 13, 2023, 03:00:09 pm »
Made an issue for this: https://github.com/opnsense/core/issues/7073 . Fingers crossed.
Show Posts
This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.
Pages: [1]
2
23.7 Legacy Series / OSPFv3 broken - MLDv2 announcements not being sent
« on: December 12, 2023, 03:09:39 pm »
I got here through a (very) old thread in the archives that describes the issues I have. Short summary:
- Trying to set up an OSPFv3 link with the ISP - Stub zone, broadcast
- Link-up works fine, neighbor status is set, routes are being announced
- After 4 minutes (reproducible) the ISP's router stops sending OSPF Hello packets, the dead interval passes and everything stops
- Restarting ospf6d makes it work again, for 4 minutes
The old thread: https://forum.opnsense.org/index.php?topic=19600.0
The remarks describing my exact symptoms:
When looking at a packet dump it is curious how there is indeed twice an MLDv2 announcement being sent, but only after restarting ospf6d and then never again:
And after these two packets, the ISP's router instantly picks up the Hello packet sending. For four minutes.
Now, reading up RFC3810:
Robustness Variable is default 2, Query Interval is default 125s, Query Response Interval default 10s. Total default is 260s. Four minutes 20 seconds, which is *precisely* what I see here.
I'm very much not familiar with these types of networks and packets - only read up on OSPFv3 last week - so question is: where is the issue? Should opnsense be sending MLDv2 announcements, but it doesn't, and this causes the MALI to expire, thereby causing my OSPFv3 router to no longer be considered a multicast listener by the other side, thereby causing a stop in hello packets?
And if yes - how do I rectify this?
- Trying to set up an OSPFv3 link with the ISP - Stub zone, broadcast
- Link-up works fine, neighbor status is set, routes are being announced
- After 4 minutes (reproducible) the ISP's router stops sending OSPF Hello packets, the dead interval passes and everything stops
- Restarting ospf6d makes it work again, for 4 minutes
The old thread: https://forum.opnsense.org/index.php?topic=19600.0
The remarks describing my exact symptoms:
Quote from: gary201
It appears that the point of failure is 4 minutes after OpnSense is rebooted.
Quote from: mjholgate
The main thing i noticed was that OPNsense doesn't appear to be sending MLDv2 announcements.
When looking at a packet dump it is curious how there is indeed twice an MLDv2 announcement being sent, but only after restarting ospf6d and then never again:
Code: [Select]
IP6 (hlim 1, next-header Options (0) payload length: 36)
fe80::20d:xxxx:yyyy:7d0d > ff02::16: HBH (padn)(rtalert: 0x0000)
[icmp6 sum ok] ICMP6, multicast listener report v2, 1 group record(s)
[gaddr ff02::5 to_ex { }]
And after these two packets, the ISP's router instantly picks up the Hello packet sending. For four minutes.
Now, reading up RFC3810:
Code: [Select]
Multicast Address Listening Interval
The Multicast Address Listening Interval (MALI) is the amount of time
that must pass before a multicast router decides there are no more
listeners of a multicast address or a particular source on a link.
This value MUST be ([Robustness Variable] times [Query Interval])
plus [Query Response Interval].
Robustness Variable is default 2, Query Interval is default 125s, Query Response Interval default 10s. Total default is 260s. Four minutes 20 seconds, which is *precisely* what I see here.
I'm very much not familiar with these types of networks and packets - only read up on OSPFv3 last week - so question is: where is the issue? Should opnsense be sending MLDv2 announcements, but it doesn't, and this causes the MALI to expire, thereby causing my OSPFv3 router to no longer be considered a multicast listener by the other side, thereby causing a stop in hello packets?
And if yes - how do I rectify this?
Pages: [1]