kernel: vxlan: non-ECT from IP_ADDRESS with TOS=0x2

admin

In our lab environment, we found these weird log in /var/log/messages

kernel: vxlan: non-ECT from IP_ADDRESS with TOS=0x2

This is kind of annoying messages and also, the vxlan tunnel networking would go wrong randomly. e.g. router: 192.168.100.1 vm1: 192.168.100.7 vm1: 192.168.100.8 private subnet connection between VMs is good (192.168.100.7 <---> 192.168.100.8)

but VM to router is no good ( 192.168.100.7 x 192.168.100.1) ( 192.168.100.8 x 192.168.100.1)

I've checked overlay network ip at compute node & network node is good (at least icmp) & neutron-l3-agent is up & running( other router can work normally)

So this is weird to us, why these troubled VMs could reach other but router?

Any advise is much appreciated.

I've had the same error. I've had no ill effects for the moment, so I've just disabled the message for the moment.

echo N | tee /sys/module/vxlan/parameters/log_ecn_error

Or by setting options vxlan log_ecn_error=N in a modprobe.d config file.