流量检测的几种方案

1/12/2008来源:网络方案人气:2733


  一、ip accounting

1、配置方法

router(config)#int s 0/0

router(config-if)#ip accounting output-packets

router#sh ip accounting output-packets

Source Destination Packets Bytes

192.1.1.110 192.1.1.97 5 500

172.17.246. 128 192.1.1.110 8 704

Accounting data age is 2d23h

或者

router(config)#int s 0/0

router(config-if)#ip accounting access-violations

router#sh ip accounting [checkpoint] access-violations

Source Destination Packets Bytes ACL

192.1.1.110 224.0.0.5 46 3128 19

Accounting data age is 7


2、说明

●此方法假如在路由器负载特大的时候请谨慎使用,因其会使系统性能下降
● 基于地址对的字节数量及数据包数量统计

● 通常只支持outbound的数据包,及被ACL拒绝的数据包(支持IN 和 OUT方向的ACL)

● 只统计穿越路由器的流量,源或目的是该路由器的数据包不做统计

● 支持所有的switching path,除了Autonomous Switching

● 可以通过SNMP来访问统计值,MIB是OLD-CISCO-IP-MIB, lipAccountingTable

● ip accounting还支持其他的监测方式,如基于tos,mac-address等

二、netflow

1、配置方法

router (config-if)#ip route-cache flow

router (config)#ip flow-eXPort destination 172.17.246.225 9996

router (config)#ip flow-export version 5 <peer-as origin-as>

Optional configuration

router (config)#ip flow-export source loopback 0

router (config)#ip flow-cache entries <1024-524288>

router (config)#ip flow-cache timeout

sh ip cache flow

IP packet size distribution (132429191 total packets):

1-32 64 96 128 160 192 224 256 288 320 352 384 416 448 480

.000 .191 .024 .009 .010 .006 .005 .008 .003 .005 .003 .003 .002 .001 .001


512 544 576 1024 1536 2048 2560 3072 3584 4096 4608

.001 .002 .107 .032 .578 .000 .000 .000 .000 .000 .000


IP Flow Switching Cache, 278544 bytes

33 active, 4063 inactive, 7975259 added

104834714 ager polls, 0 flow alloc failures

Active flows timeout in 30 minutes

Inactive flows timeout in 15 seconds

last clearing of statistics never

PRotocol Total Flows Packets Bytes Packets Active(Sec) Idle(Sec)

-------- Flows /Sec /Flow /Pkt /Sec /Flow /Flow

TCP-Telnet 25378 0.0 12 652 0.0 22.9 15.2

TCP-FTP 432435 0.1 4 59 0.4 1.2 2.7

TCP-FTPD 28670 0.0 212 1397 1.4 8.2 1.6

TCP-WWW 4682530 1.0 15 927 16.4 2.4 4.6

2、说明

● 统计基于流(包括地址对、端口号、协议类型等)的数据量

● 只支持inbound的流量

● 只支持单播

● 只能在主端口配置

● 需要和cef或fast switching一起使用

● 对路由器性能有影响

10,000 active flows: < 4% of additional CPU utilization

45,000 active flows: <12% of additional CPU utilization

65,000 active flows: <16% of additional CPU utilization进入讨论组讨论。

  三、NBAR

1、配置方法

router(config)# interface FastEthernet 0/1

router(config-if)# ip nbar protocol discovery

router# show ip nbar protocol -discovery interface FastEthernet 6/0

FastEthernet6/0

Input Output

Protocol Packet Count Packet Count

Byte Count Byte Count

5 minute bit rate (bps) 5 minute bit rate (bps)

------------------------ ------------------------ ------------------------

http 316773 0

26340105 0

3000 0

pop3 4437 7367

2301891 339213

3000 0

snmp 279538 14644

319106191 673624

0 0



Total 17203819 151684936

19161397327 50967034611

4179000 6620000


2、说明

● NBAR识别从4层到7层的协议信息

●可以基于端口统计input 和output 的bit rate (bps), packet counts, byte counts

● 只能在cef或dcef的基础上运行

● 不象netflow,没有流的概念。主要是统计目前网络中有那一些应用


四、access-list log

1、配置方法

router(config)# access-list 118 permit ip any any log

router(config)# interface FastEthernet 0/1

router(config-if)# ip access-group 118 out

router# show log

router>sh log

Syslog logging: enabled (0 messages dropped, 0 messages rate-limited, 0 flushes,

0 overruns)

Console logging: level debugging, 79 messages logged

Monitor logging: level debugging, 0 messages logged

Buffer logging: level debugging, 79 messages logged

Logging Exception size (4096 bytes)

Trap logging: level informational, 83 message lines logged


Log Buffer (4096 bytes):


*May 25 05:27:50: %SEC-6-IPACCESSLOGP: list 118 permitted tcp 10.1.64.71(0) -> 10.0.29.3(0), 1 packet

*May 25 05:28:59: %SEC-6-IPACCESSLOGP: list 118 permitted tcp 10.1.64.71(0) -> 10.0.28.128(0), 1 packet

*May 25 05:29:19: %SEC-6-IPACCESSLOGP: list 118 permitted tcp 10.1.64.71(0) -> 10.0.29.3(0), 56 packets进入讨论组讨论。