IPv6 always getting disabled on bridge after a couple of days


New Member
Sep 21, 2022
If have have the following setup:

auto eno3
iface eno3 inet manual
iface eno3 inet6 manual
#TRUNK interface

iface eno3.101 inet manual
iface eno3.101 inet6 manual
#proxmox interface

auto vmbr0
iface vmbr0 inet manual
        bridge-ports eno3
        bridge-stp off
        bridge-fd 0

auto vmbr0v101
iface vmbr0v101 inet dhcp
       bridge-ports eno3.101
       bridge-stp off

iface vmbr0v101 inet6 manual
        accept_ra 2
        up sleep 5
        up dhclient -1 -6 -cf /etc/dhcp/dhclient6.conf -lf /var/lib/dhcp/dhclient6.vmbr0v101.leases -v vmbr0v101 || true

eno3 has multiple vlans (101,102,103) for VMs and containers and I the proxmox ui should be accessible on vlan 101.
This works so far, but `net.ipv6.conf.vmbr0v101.disable_ipv6` always gets set to 1 after some time and I have to login to set it to 0 again.

I tried to use macvlan or a vlan aware bridge but so far failed to get something working reliably.


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