For help in a vm virtual machine a has a physical address 192.168.0.1, virtual machine installed openv switch, and the docker engine, I will the virtual network adapter by veth docker container received ovs virtual switches, ovs configured with a type on the virtual switch port for vxlan, ping in containers another container in the vm b address, in accordance with the principle of vxlan need three layers of lining ping packets to udp encapsulation, and now there is a question that encapsulate IP layer is how to determine the source address, I found using the physical address 192.168.0.1 by tcpdump, vxlan why use this address to set the outer package, if there are multiple physical address on the vm, that how to choose again, please know that the great god solve,