参考链接：https://www.cnblogs.com/zqyanywn/p/10501590.html
1. fdb/show bridge 列出指定桥上每个MAC直至与VLAN的对应信息，并且包含该学习到该MAC的端口号还有该条目的age信息，单位为秒
[root@ostack1 ~]# ovs-appctl fdb/show br-eth1 port VLAN MAC Age 1 4 fa:16:3e:e2:af:d7 225 1 200 fa:16:3e:12:d2:92 145 2 0 fa:16:3e:ef:95:a9 89 2 0 fa:16:3e:0e:74:20 39 1 256 fa:16:3e:0a:2c:4a 8 1 256 fa:16:3e:d6:4d:7d 8 1 256 fa:16:3e:20:cf:bf 8 1 256 fa:16:3e:7a:1c:9c 8 1 256 fa:16:3e:ff:78:24 8 1 256 fa:16:3e:ec:54:5f 7 1 256 fa:16:3e:2e:ff:f5 7 1 256 fa:16:3e:f4:fb:9d 7 2 256 0c:c6:cc:f9:07:76 1 1 256 fa:16:3e:90:a0:11 1 3 256 52:54:00:b8:dc:37 0 1 256 fa:16:3e:e2:af:d7 0
2.fdb/flush [bridge]
清除指定桥的MAC学习表，没有指定桥则应用于所有桥
3.bridge/dump-flows bridge 列出桥上所有的流，包括那些在其他命令中（例如 ovs-ofctl dump-flows）默认隐藏的流.一些机制比如带内管理等设置的流策略是不行允许修改和覆盖的，所以对控制器来说他们是隐藏的。
[root@ostack1 ~]# ovs-appctl bridge/dump-flows br-eth3 duration=306s, n_packets=52, n_bytes=2336, priority=2,in_port=2,actions=resubmit(,1) duration=325s, n_packets=329, n_bytes=22978, priority=0,actions=NORMAL duration=306s, n_packets=5574, n_bytes=387046, priority=1,actions=resubmit(,3) table_id=1, duration=306s, n_packets=51, n_bytes=2294, priority=0,actions=resubmit(,2) table_id=2, duration=305s, n_packets=51, n_bytes=2294, priority=2,in_port=2,actions=drop table_id=3, duration=305s, n_packets=5563, n_bytes=386275, priority=1,actions=NORMAL table_id=254, duration=10276157s, n_packets=0, n_bytes=0, priority=2,recirc_id=0,actions=drop table_id=254, duration=10276157s, n_packets=0, n_bytes=0, priority=0,reg0=0x1,actions=controller(reason=no_match) table_id=254, duration=10276157s, n_packets=31, n_bytes=8887, priority=0,reg0=0x2,actions=drop table_id=254, duration=10276157s, n_packets=0, n_bytes=0, priority=0,reg0=0x3,actions=drop