一：实现流量监控
（一）流量监控原理
其中控制器向交换机周期下发获取统计消息，请求交换机消息------是主动下发过程
流速公式：是（t1时刻的流量-t0时刻的流量）/（t1-t0)
剩余带宽公式：链路总带宽-流速--------是这一个这一个,例如s2-s3（不是一条，例如：h1->s1->s2->s3->h2）的剩余带宽
路径有效带宽是只：这一整条路径中，按照最小的剩余带宽处理
二：代码实现
（一）代码框架
from ryu.app import simple_switch_13 from ryu.controller.handler import set_ev_cls from ryu.controller import ofp_event from ryu.controller.handler import MAIN_DISPATCHER,DEAD_DISPATCHER class MyMonitor(simple_switch_13): #simple_switch_13 is same as the last experiment which named self_learn_switch ''' design a class to achvie managing the quantity of flow ''' def __init__(self,*args,**kwargs): super(MyMonitor,self).__init__(*args,**kwargs) @set_ev_cls(ofp_event.EventOFPStateChange,[MAIN_DISPATCHER,DEAD_DISPATCHER]) def _state_change_handler(self,ev): ''' design a handler to get switch state transition condition ''' pass def _monitor(self): ''' design a monitor on timing system to request switch infomations about port and flow ''' pass def _request_stats(self,datapath): ''' the function is to send requery to datapath ''' pass @set_ev_cls(ofp_event.EventOFPPortStatsReply,MAIN_DISPATCHER) def _port_stats_reply_handler(self,ev): ''' monitor to require the port state, then this function is to get infomation for port`s info ''' pass @set_ev_cls(ofp_event.EventOFPFlowStatsReply,MAIN_DISPATCHER) def _port_stats_reply_handler(self,ev): ''' monitor to require the flow state, then this function is to get infomation for flow`s info ''' pass
（二）推文：协程https://www.cnblogs.com/ssyfj/p/9030165.html
（三）全部代码实现
from operator import attrgetter from ryu.app import simple_switch_13 from ryu.controller.handler import set_ev_cls from ryu.controller import ofp_event from ryu.controller.handler import MAIN_DISPATCHER,DEAD_DISPATCHER from ryu.lib import hub class MyMonitor(simple_switch_13.SimpleSwitch13): #simple_switch_13 is same as the last experiment which named self_learn_switch ''' design a class to achvie managing the quantity of flow ''' def __init__(self,*args,**kwargs): super(MyMonitor,self).__init__(*args,**kwargs) self.datapaths = {} #use gevent to start monitor self.monitor_thread = hub.spawn(self._monitor) @set_ev_cls(ofp_event.EventOFPStateChange,[MAIN_DISPATCHER,DEAD_DISPATCHER]) def _state_change_handler(self,ev): ''' design a handler to get switch state transition condition ''' #first get ofprocotol info datapath = ev.datapath ofproto = datapath.ofproto ofp_parser = datapath.ofproto_parser #judge datapath`s status to decide how to operate if datapath.state == MAIN_DISPATCHER: #should save info to dictation if datapath.id not in self.datapaths: self.datapaths[datapath.id] = datapath self.logger.debug("Regist datapath: %16x",datapath.id) elif datapath.state == DEAD_DISPATCHER: #should remove info from dictation if datapath.id in self.datapaths: del self.datapaths[datapath.id] self.logger.debug("Unregist datapath: %16x",datapath.id) def _monitor(self): ''' design a monitor on timing system to request switch infomations about port and flow ''' while True: #initiatie to request port and flow info all the time for dp in self.datapaths.values(): self._request_stats(dp) hub.sleep(5) #pause to sleep to wait reply, and gave time to other gevent to request def _request_stats(self,datapath): ''' the function is to send requery to datapath ''' self.logger.debug("send stats reques to datapath: %16x for port and flow info",datapath.id) ofproto = datapath.ofproto parser = datapath.ofproto_parser req = parser.OFPFlowStatsRequest(datapath) datapath.send_msg(req) req = parser.OFPPortStatsRequest(datapath, 0, ofproto.OFPP_ANY) datapath.send_msg(req) @set_ev_cls(ofp_event.EventOFPPortStatsReply,MAIN_DISPATCHER) def _port_stats_reply_handler(self,ev): ''' monitor to require the port state, then this function is to get infomation for port`s info print("6666666666port info:") print(ev.msg) print(dir(ev.msg)) ''' body = ev.msg.body self.logger.info('datapath port ' 'rx_packets tx_packets' 'rx_bytes tx_bytes' 'rx_errors tx_errors' ) self.logger.info('--------------- --------' '-------- --------' '-------- --------' '-------- --------' ) for port_stat in sorted(body,key=attrgetter('port_no')): self.logger.info('%016x %8x %8d %8d %8d %8d %8d %8d', ev.msg.datapath.id,port_stat.port_no,port_stat.rx_packets,port_stat.tx_packets, port_stat.rx_bytes,port_stat.tx_bytes,port_stat.rx_errors,port_stat.tx_errors ) @set_ev_cls(ofp_event.EventOFPFlowStatsReply,MAIN_DISPATCHER) def _flow_stats_reply_handler(self,ev): ''' monitor to require the flow state, then this function is to get infomation for flow`s info print("777777777flow info:") print(ev.msg) print(dir(ev.msg)) ''' body = ev.msg.body self.logger.info('datapath ' 'in_port eth_src' 'out_port eth_dst' 'packet_count byte_count' ) self.logger.info('--------------- ' '---- -----------------' '---- -----------------' '--------- ---------' ) for flow_stat in sorted([flow for flow in body if flow.priority==1], key=lambda flow:(flow.match['in_port'],flow.match['eth_src'])): self.logger.info('%016x %8x %17s %8x %17s %8d %8d', ev.msg.datapath.id,flow_stat.match['in_port'],flow_stat.match['eth_src'], flow_stat.instructions[0].actions[0].port,flow_stat.match['eth_dst'], flow_stat.packet_count,flow_stat.byte_count )
补充：注意---每个事件的属性可能不同，需要我们进行Debug，例如上面就出现了ev.msg.body（之前hub实现中没有）
（四）代码讲解
1.class MyMonitor(simple_switch_13.SimpleSwitch13):
simple_switch_13.SimpleSwitch13是样例代码，其中实现了和我们上一次实验中，自学习交换机类似的功能
（稍微多了个关于交换机是否上传全部packet还是只上传buffer_id），所以我们直接继承，可以减少写代码时间
2.协程实现伪并发self.monitor_thread = hub.spawn(self._monitor)
def __init__(self,*args,**kwargs): super(MyMonitor,self).__init__(*args,**kwargs) self.datapaths = {} #use gevent to start monitor self.monitor_thread = hub.spawn(self._monitor)
3.在协程中实现周期请求交换机信息
def _monitor(self): ''' design a monitor on timing system to request switch infomations about port and flow ''' while True: #initiatie to request port and flow info all the time for dp in self.datapaths.values(): self._request_stats(dp) hub.sleep(5) #pause to sleep to wait reply, and gave time to other gevent to request
4.主动下发消息，请求交换机信息OFPFlowStatsRequest------注意：我们这里请求两个（端口和协议信息），所以我们要使用两个函数来分别处理port和flow响应
def _request_stats(self,datapath):
'''
the function is to send requery to datapath
'''
self.logger.debug("send stats reques to datapath: %16x for port and flow info",datapath.id)
ofproto = datapath.ofproto
parser = datapath.ofproto_parser
req = parser.OFPFlowStatsRequest(datapath)
datapath.send_msg(req)
req = parser.OFPPortStatsRequest(datapath, 0, ofproto.OFPP_ANY) #可以向上面一样省略默认参数
datapath.send_msg(req)
源码查看参数
@_set_stats_type(ofproto.OFPMP_FLOW, OFPFlowStats) @_set_msg_type(ofproto.OFPT_MULTIPART_REQUEST) class OFPFlowStatsRequest(OFPFlowStatsRequestBase): """ Individual flow statistics request message The controller uses this message to query individual flow statistics. ================ ====================================================== Attribute Description ================ ====================================================== flags Zero or ``OFPMPF_REQ_MORE`` table_id ID of table to read out_port Require matching entries to include this as an output port out_group Require matching entries to include this as an output group cookie Require matching entries to contain this cookie value cookie_mask Mask used to restrict the cookie bits that must match match Instance of ``OFPMatch`` ================ ====================================================== Example:: def send_flow_stats_request(self, datapath): ofp = datapath.ofproto ofp_parser = datapath.ofproto_parser cookie = cookie_mask = 0 match = ofp_parser.OFPMatch(in_port=1) req = ofp_parser.OFPFlowStatsRequest(datapath, 0, ofp.OFPTT_ALL, ofp.OFPP_ANY, ofp.OFPG_ANY, cookie, cookie_mask, match) datapath.send_msg(req) """ def __init__(self, datapath, flags=0, table_id=ofproto.OFPTT_ALL, out_port=ofproto.OFPP_ANY, out_group=ofproto.OFPG_ANY, cookie=0, cookie_mask=0, match=None, type_=None):
5.获取端口响应信息ofp_event.EventOFPPortStatsReply
@set_ev_cls(ofp_event.EventOFPPortStatsReply,MAIN_DISPATCHER) def _port_stats_reply_handler(self,ev): ''' monitor to require the port state, then this function is to get infomation for port`s info print("6666666666port info:") print(ev.msg) print(dir(ev.msg)) ''' body = ev.msg.body self.logger.info('datapath port ' 'rx_packets tx_packets' 'rx_bytes tx_bytes' 'rx_errors tx_errors' ) self.logger.info('--------------- --------' '-------- --------' '-------- --------' '-------- --------' ) for port_stat in sorted(body,key=attrgetter('port_no')): self.logger.info('%016x %8x %8d %8d %8d %8d %8d %8d', ev.msg.datapath.id,port_stat.port_no,port_stat.rx_packets,port_stat.tx_packets, port_stat.rx_bytes,port_stat.tx_bytes,port_stat.rx_errors,port_stat.tx_errors )
端口信息：《参考》
6666666666port info: version=0x4,msg_type=0x13,msg_len=0x1d0,xid=0x8dcd9187, OFPPortStatsReply( body=[ OFPPortStats(port_no=4294967294,rx_packets=0,tx_packets=0,rx_bytes=0,tx_bytes=0,rx_dropped=65,tx_dropped=0,rx_errors=0,tx_errors=0,rx_frame_err=0,rx_over_err=0,rx_crc_err=0,collisions=0,duration_sec=1912,duration_nsec=331000000), OFPPortStats(port_no=1,rx_packets=154,tx_packets=225,rx_bytes=11660,tx_bytes=19503,rx_dropped=0,tx_dropped=0,rx_errors=0,tx_errors=0,rx_frame_err=0,rx_over_err=0,rx_crc_err=0,collisions=0,duration_sec=1912,duration_nsec=333000000), OFPPortStats(port_no=2,rx_packets=186,tx_packets=257,rx_bytes=14516,tx_bytes=22343,rx_dropped=0,tx_dropped=0,rx_errors=0,tx_errors=0,rx_frame_err=0,rx_over_err=0,rx_crc_err=0,collisions=0,duration_sec=1912,duration_nsec=334000000), OFPPortStats(port_no=3,rx_packets=220,tx_packets=232,rx_bytes=18439,tx_bytes=19311,rx_dropped=0,tx_dropped=0,rx_errors=0,tx_errors=0,rx_frame_err=0,rx_over_err=0,rx_crc_err=0,collisions=0,duration_sec=1912,duration_nsec=333000000) ] ,flags=0,type=4) OFPPortStats( port_no=4294967294, ---------- rx_packets=0, ---------- tx_packets=0, ---------- rx_bytes=0, ---------- tx_bytes=0, ---------- rx_dropped=65, tx_dropped=0, rx_errors=0, ---------- tx_errors=0, ---------- rx_frame_err=0, rx_over_err=0, rx_crc_err=0, collisions=0, duration_sec=1912, duration_nsec=331000000) ['_STATS_MSG_TYPES', '_TYPE', '__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', '_base_attributes', '_class_prefixes', '_class_suffixes', '_decode_value', '_encode_value', '_get_decoder', '_get_default_decoder', '_get_default_encoder', '_get_encoder', '_get_type', '_is_class', '_opt_attributes', '_restore_args', '_serialize_body', '_serialize_header', '_serialize_pre', 'body', 'buf', 'cls_body_single_struct', 'cls_from_jsondict_key', 'cls_msg_type', 'cls_stats_body_cls', 'cls_stats_type', 'datapath' ---------- , 'flags', 'from_jsondict', 'msg_len', 'msg_type', 'obj_from_jsondict', 'parser', 'parser_stats', 'parser_stats_body', 'register_stats_type', 'serialize', 'set_buf', 'set_classes', 'set_headers', 'set_xid', 'stringify_attrs', 'to_jsondict', 'type', 'version', 'xid']
6.获取flow协议响应信息ofp_event.EventOFPFlowStatsReply
@set_ev_cls(ofp_event.EventOFPFlowStatsReply,MAIN_DISPATCHER) def _flow_stats_reply_handler(self,ev): ''' monitor to require the flow state, then this function is to get infomation for flow`s info print("777777777flow info:") print(ev.msg) print(dir(ev.msg)) ''' body = ev.msg.body self.logger.info('datapath ' 'in_port eth_src' 'out_port eth_dst' 'packet_count byte_count' ) self.logger.info('--------------- ' '---- -----------------' '---- -----------------' '--------- ---------' ) for flow_stat in sorted([flow for flow in body if flow.priority==1], key=lambda flow:(flow.match['in_port'],flow.match['eth_src'])): self.logger.info('%016x %8x %17s %8x %17s %8d %8d', ev.msg.datapath.id,flow_stat.match['in_port'],flow_stat.match['eth_src'], flow_stat.instructions[0].actions[0].port,flow_stat.match['eth_dst'], flow_stat.packet_count,flow_stat.byte_count )
协议信息《参考》
777777777flow info: version=0x4,msg_type=0x13,msg_len=0x200,xid=0x9e448a1a, OFPFlowStatsReply( body=[ OFPFlowStats(byte_count=5446,cookie=0,duration_nsec=552000000,duration_sec=1893,flags=0,hard_timeout=0,idle_timeout=0,instructions=[OFPInstructionActions(actions=[OFPActionOutput(len=16,max_len=65509,port=1,type=0)],len=24,type=4)], length=104,match=OFPMatch(oxm_fields={'in_port': 2, 'eth_src': '8a:06:6a:2c:10:fc', 'eth_dst': '26:20:2f:85:5a:9a'}),packet_count=71,priority=1,table_id=0), OFPFlowStats(byte_count=5348,cookie=0,duration_nsec=549000000,duration_sec=1893,flags=0,hard_timeout=0,idle_timeout=0,instructions=[OFPInstructionActions(actions=[OFPActionOutput(len=16,max_len=65509,port=2,type=0)],len=24,type=4)], length=104,match=OFPMatch(oxm_fields={'in_port': 1, 'eth_src': '26:20:2f:85:5a:9a', 'eth_dst': '8a:06:6a:2c:10:fc'}),packet_count=70,priority=1,table_id=0), OFPFlowStats(byte_count=8302,cookie=0,duration_nsec=438000000,duration_sec=1887,flags=0,hard_timeout=0,idle_timeout=0,instructions=[OFPInstructionActions(actions=[OFPActionOutput(len=16,max_len=65509,port=1,type=0)],len=24,type=4)], length=104,match=OFPMatch(oxm_fields={'in_port': 2, 'eth_src': 'ca:9e:a1:af:b9:5f', 'eth_dst': '26:20:2f:85:5a:9a'}),packet_count=103,priority=1,table_id=0), OFPFlowStats(byte_count=8204,cookie=0,duration_nsec=436000000,duration_sec=1887,flags=0,hard_timeout=0,idle_timeout=0,instructions=[OFPInstructionActions(actions=[OFPActionOutput(len=16,max_len=65509,port=2,type=0)],len=24,type=4)] ,length=104,match=OFPMatch(oxm_fields={'in_port': 1, 'eth_src': '26:20:2f:85:5a:9a', 'eth_dst': 'ca:9e:a1:af:b9:5f'}),packet_count=102,priority=1,table_id=0), OFPFlowStats(byte_count=6739,cookie=0,duration_nsec=807000000,duration_sec=9,flags=0,hard_timeout=0,idle_timeout=0,instructions=[OFPInstructionActions(actions=[OFPActionOutput(len=16,max_len=65535,port=4294967293,type=0)],len=24,type=4)], length=80,match=OFPMatch(oxm_fields={}),packet_count=74,priority=0,table_id=0) ] ,flags=0,type=1) OFPFlowStats( byte_count=5446, ---------- cookie=0, duration_nsec=552000000, duration_sec=1893, flags=0, hard_timeout=0, idle_timeout=0, instructions=[ OFPInstructionActions( actions=[ OFPActionOutput( len=16, max_len=65509, port=1, ---------- type=0) ], len=24, type=4 ) ], length=104, match=OFPMatch(oxm_fields={ 'in_port': 2, ---------- 'eth_src': '8a:06:6a:2c:10:fc', ---------- 'eth_dst': '26:20:2f:85:5a:9a' ---------- }), packet_count=71, ---------- priority=1, table_id=0 ) ['_STATS_MSG_TYPES', '_TYPE', '__class__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', '_base_attributes', '_class_prefixes', '_class_suffixes', '_decode_value', '_encode_value', '_get_decoder', '_get_default_decoder', '_get_default_encoder', '_get_encoder', '_get_type', '_is_class', '_opt_attributes', '_restore_args', '_serialize_body', '_serialize_header', '_serialize_pre', 'body', 'buf', 'cls_body_single_struct', 'cls_from_jsondict_key', 'cls_msg_type', 'cls_stats_body_cls', 'cls_stats_type', 'datapath' ---------- , 'flags', 'from_jsondict', 'msg_len', 'msg_type', 'obj_from_jsondict', 'parser', 'parser_stats', 'parser_stats_body', 'register_stats_type', 'serialize', 'set_buf', 'set_classes', 'set_headers', 'set_xid', 'stringify_attrs', 'to_jsondict', 'type', 'version', 'xid']
三：实验演示
（一）开启Ryu
ryu-manager my_monitor.py
（二）开启Mininet
sudo mn --topo=tree,2,2 --controller=remote --mac
(三）Ryu显示结果
