LXC bridge issue with networkd on CentOS 7

[Satish Patel]

Last week, I built OSA using networkd style networking /etc/systemd/network/ to make it more efficient and found my container not pinging outside world (NATing isn't working at all) they can ping each other but not outside world or LAN.

Later i removed networkd and move all network configuration into /etc/sysconfig/network-script/ifcfg-* and everything start working, i did this test on couple of machine to make sure its not my LAN issue or my host issue.

It seems CentOS 7.x comes with systemd 219 and it seems its buggy, I am opening this ticket to find out if anyone else experiencing same issue.

I would say we should update in documentation with soft notes so people like me won't waste 3 days to dig this issue.

[Jonathan Rosser (jrosser)]

This is not directly a bug with OSA but in the host setup. It is however worth noting that a very similar issue occured in the openstack CI which was resolved with this patch.

https://github.com/openstack/ansible-role-systemd_networkd/commit/242b3c3fb4a3f8ebeba5c24cf8c7a510cba14143

In the case of the openstack CI br-vlan would not inherit forwarding=1 from the global setting and it had to be specifically applied in the network configuration.