OFPST_PORT_DESC reply (xid=0x2):
 1(enp4s0): addr:fa:16:3e:39:ef:4e
     config:     0
     state:      0
     speed: 0 Mbps now, 0 Mbps max
 2(vlan22): addr:f2:73:68:32:d2:81
     config:     0
     state:      0
     speed: 0 Mbps now, 0 Mbps max
 3(vlan20): addr:b6:60:07:44:a8:b3
     config:     0
     state:      0
     speed: 0 Mbps now, 0 Mbps max
 4(vlan21): addr:c2:3b:c9:ff:5c:fa
     config:     0
     state:      0
     speed: 0 Mbps now, 0 Mbps max
 LOCAL(br-ex): addr:fa:16:3e:39:ef:4e
     config:     0
     state:      0
     speed: 0 Mbps now, 0 Mbps max
