IPv6 Probleme (evtl. Proxmox-Problematik!)

[m-electronics]

Hallo an die Proxmox-Community,

Ich brauche Schwarmwissen, denn seit ein paar Wochen (fällt es mir zumindest auf) kann ich von Clients hinter einer Router-VM die IP des Routers (`prefix::`) nicht mehr pingen. Und nach Paketanalyse auf der Bridge und auf den VMs selbst, gehen zu dieser IP auch gar keine ICMPv6-Echo-Request-Pakete raus.
Es kommt aber nicht einfach keine Antwort (bzw. das hatte ich jetzt auch schon), sondern stattdessen antwortet der Host von dem der Ping läuft selbst auf den Ping mit seiner IPv6-Addresse auf dem Interface. Und ich dachte erst es liegt an diesem speziellen Router, nämlich MikroTik, aber da es mit VyOS nun auch nicht funktioniert, muss es ja irgendwas auf dem Layer darunter sein.

Wenn jemand eine Idee hat, gerne antworten.
Ich bin mit meinem Latein am Ende.

 

[ggoller]

Hi!
so does the ping succeed or not? how is the interface of your client vm configured?

(note that this is the english forum, the german one is here: https://forum.proxmox.com/forums/proxmox-ve-deutsch-german.20/)

 

[m-electronics]

Hi!
so does the ping succeed or not? how is the interface of your client vm configured?

(note that this is the english forum, the german one is here: https://forum.proxmox.com/forums/proxmox-ve-deutsch-german.20/)

Oh I didn´t see that with the language because in the proxmox datacenter manager forum was also answered in German.
But for your question: The pings succeeds, but the ping answer comes from a wrong IP address. From the IPv6 address host address itself.
The interface is configured normally with a IPv6 address in a /68 subnet (yes, that works) and a default route to the IPv6 address of the router VM.

 

[m-electronics]

No help here anymore? Or did I understand something wrong?

 

[ggoller]

could you post your routes here and the ping command you used?

 

[m-electronics]

could you post your routes here and the ping command you used?

I can do that
1. Ping (DIFFERENT ADDRESS warning!)

2. Routes

And I captured the packets outgoing and coming in on the pfSense machine, and no echo requests are there, but Neighbor Solictitation messages to that aren´t a advertisement message is there as reply, so like the pfSense doesn´t have this address. But this is only with that address `::`, with `::1` I don´t have this problem. And I don´t change anything on my config, only update proxmox and then it must began.

 

[ggoller]

Hi!
could you also send me the tcpdump and the interface configuration of ens18 here and on the router?

 

[m-electronics]

Hi!
could you also send me the tcpdump and the interface configuration of ens18 here and on the router?

I upgraded now the proxmox. At the moment it is working but I don´t know how long that will be so. But I´m now unsure what the originator was.

 

[m-electronics]

The working state was not for a long time
On my other proxmox node (not upgraded, but I didn´t see anything in the updates that is associated with networking) it is the same issue.
And now I have more details: The neighbor solicitation points to a wrong MAC address!
There are more than one device in the same network that is joining the solicited node multicast group address. Reason: ???
The right device also joins it, but doesn´t answer to the neighbor solicitation. The wrong device answers!

Neighbor solicitation:

Neighbor advertisement from wrong address:

(I can´t attach a .pcapng file here)

Interface Configuration:
1. On the client:

2. On the router (pfSense):