Linux bridge not passing IPv6


Active Member
Apr 17, 2017
Dear fellows,

using Proxmox 6.0 and 6.1 I have the problem that IPv6 is not passed to the VMs. It does not matter if LXC container or KVM.
So it looks like the bridge filters IPv6. It sometimes works right after boot but a couple of minutes later it is blocked again.

My interfaces is very simple:
auto lo
iface lo inet loopback

iface eno1 inet manual

iface eno2 inet manual

iface eno3 inet manual

iface eno4 inet manual

iface enp1 inet manual

auto vmbr0
iface vmbr0 inet static
    netmask  24
    bridge-ports enp1
    bridge-stp off
    bridge-fd 0
    bridge-vlan-aware yes
    bridge-vids 2-4094

On the same system I am using open vswitch and everything works fine.

Is there anything special on using Linux bridge with IPv6 clients?

I know this is old but I seem to be running across the same problem. I had run ovs a couple years ago but switched to linux bridge because multicast didn't seem to work correctly for some of my needs. I can't remember when I had ipv6 working the last time.


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