[SOLVED] SSH is inaccessible over IPv6 on thunderbolt interfaces?


Active Member
Aug 8, 2023
I setup a promox v8 cluster.

I have 3 nodes where NIC 1 is connected to a LAN - this is purely using IPv4.
NIC2 (thunderbolt direct connection) on each node are purely using IPv6

  • I can ping -6 node 3 from node 1.
  • I can curl the 8006 port on node 3 from node 1 over IPv6 ok
  • I can't access SSH port 22 on node 3 from node 1

I checked:
  1. that sshd is listening on both and ::
  2. that the firewall is off at the cluster level and that there are no IPTables whatsoever

At this point i am stumped (but i am new to proxmox...)
This is also affecting ceph on port 3300 - i can see it is listening on <ipv6add>:3300 and a bunch of other ports, but when i setup node two of ceph i get "Could not connect to ceph cluster despite configured monitors" and i get no connection if i try and curl the ports.

I am stumped.
This seems to be caused by a bug when only using thunderbolt interfaces.

Marking as solved as I now know the cause.


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