linux中vlan 设备，eth/ens设备，bridge设备，veth设备, tap设备，tun设备

https://blog.csdn.net/sinat_20184565/article/details/80704355
https://developers.redhat.com/blog/2017/09/14/vlan-filter-support-on-bridge#without_vlan_filtering

命令：
ip addr add 3.3.3.5/24 dev brg-o
ip link add veth0 type veth peer name veth1
ip addr add 3.3.3.3/24 dev veth0
ip addr add 3.3.3.4/24 dev veth1
ip link set veth0 up
ip link set veth1 up
ip link set dev veth0 master brg-o
ip link set dev veth0 master brg-o
ip route add default via 192.16