Ubuntu – Ipv6 over bridged network stops working after some time (Ubuntu LXC)

bridgeipv6lxcUbuntu

i hope you can help me. I am running several Linux Containers on a bare metal server which is provided with an Global Ipv6 address as well as an 64-bit network by my provider.

I have configured IPv6 settings within the config files of each container using a bridge provided by the host machine. When I reboot the whole system I am able to access my containers via IPv6 and vice versa (e.g. ping6 google.de works). After some time (dunno how long) the containers are no more accessible via their ipv6-address and I don't know why (ping6 google.de also doesn't work). Does anyone have a clue what could cause this behavior?

Here are my configs:

network/interfaces (master)

iface br0 inet6 static
pre-up modprobe ipv6
address 2a02:xxxx:1:1::517:f79
gateway 2a02:xxxx:1:1::1
netmask 64
bridge_stp on

sysctl.conf (master)

ipv6 settings (no autoconfiguration)

net.ipv6.conf.default.autoconf=0
net.ipv6.conf.default.accept_ra=0
net.ipv6.conf.default.accept_ra_defrtr=0
net.ipv6.conf.default.accept_ra_rtr_pref=0
net.ipv6.conf.default.accept_ra_pinfo=0
net.ipv6.conf.default.accept_source_route=0
net.ipv6.conf.default.accept_redirects=0
net.ipv6.conf.default.forwarding=1
net.ipv6.conf.default.proxy_ndp=1
net.ipv6.conf.all.autoconf=0
net.ipv6.conf.all.accept_ra=0
net.ipv6.conf.all.accept_ra_defrtr=0
net.ipv6.conf.all.accept_ra_rtr_pref=0
net.ipv6.conf.all.accept_ra_pinfo=0
net.ipv6.conf.all.accept_source_route=0
net.ipv6.conf.all.accept_redirects=0
net.ipv6.conf.all.forwarding=1
net.ipv6.conf.all.proxy_ndp=1

network/interfaces (container)

The loopback network interface

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet manual
iface eth0 inet6 manual

LXC-Container config

Network configuration

  • lxc.network.type = veth
  • lxc.network.flags = up
  • lxc.network.link = br0
  • lxc.network.hwaddr = 7e:7f:de:16:xx:xx
  • lxc.network.ipv4.gateway = 81.7.xx.1
  • lxc.network.ipv4 = 81.7.xx.xxx/24
  • lxc.network.ipv6 = 2a02:xxxx:a:77::123/64

I would be very thankful for any advice.

Best,
Patrick

Best Answer

Try disabling multicast snooping:

echo -n 0 > /sys/class/net/<brif>/bridge/multicast_snooping

Or enabling multicast querier (very early):

echo -n 1 > /sys/class/net/<brif>/bridge/multicast_querier

https://askubuntu.com/a/688854/11831