QOS实验

QOS

一、描述

QOS：策略设置，一般分为几个步骤

第一：分类流量

      1.1.1、根据IP地址分类，配制的时候使用ACL访问控制列表

      1.1.2、根据思科NBAR[nba:]来分类，它可以根据七层来识别

Router(config)#class-map map名

Router(config-cmap)#match ?
    access-group          Access group
    any                   Any packets
    class-map             Class map
    cos                   IEEE 802.1Q/ISL class of service/user priority values
    destination-address   Destination address
    input-interface       Select an input interface to match
    ip                    IP specific values
    mpls                  Multi Protocol Label Switching specific values
    not                   Negate this match result
    protocol              Protocol         /NBAR
    qos-group             Qos-group
    source-address        Source address

第二：标记流量（marking）

     标记可以基于二层ip precedenc（IP优先级）也可以基于三层DSCP来标记识别的流量

     一般在标记的时候分为几大块：语音流、视频流、重要业务流、其它业务流分为从0－7这么几个级别

7和6保留0也保留

级别  流量种类   dscp标记      实例

5      语音        ef          voip

4      流媒体      af4x        视频会议等

3      业务流量    af3x        ERP、SQL等办公系统

2      传统流量    af2x        mail、ftp、web等

1      垃圾流量    af1x        抢占带宽的流量例：bt,迅雷，ppstream等

注：x代表(1-9)是同一个级别内在分类

设置

policy-map 名称
  class-map 名称
      set ip dscp {DSCP}
      set ip precedence {PRECEDENCE}
      set cos {COS}
设置标记

  

第三：设置策略

在policy-map下，匹配class-map后

priority {Kbps|percent PERCENT} [bc]    定义优先级流量的带宽以及突发流量
bandwidth {Kbps|percent PERCENT}        定义保留带宽
random-detect                           启用WRED
police {CIR BC BE} conform-action {action} exceed-action {action} [violated-action {action}]  使用令牌桶限速
queue-limit {PACKETS}                   定义队列中数据报的最大个数
service-policy {policy-name}            调用其它的策略进行嵌套
shape {average|peak} {CIR [BC] [BE]}    整形
drop                                    丢弃

第四：在接口上应用

Router(config-if)#service-policy {input|output} {policy_map名字}

  input    设置在进口上
  output   设置在出口上

注：如果对QOS不太懂建议看  http://www.blogcn.com/User5/ghol/blog/51036470.html  是一个哥儿们写的笔记很不错

二、拓扑

图中，COM路由器接内网，ISP路由器是模拟的外网，R2属于边界路由器

三、实验说明

我们在R2的s1/0和s1/1口上配制接口带宽为 16Kbit/s，然后在s1/0即进口上做标记，

标记为，满足条件打20的标记，超出的打10的标记。

在s1/1出口上做策略对于打了10标记的流量，做相应的drop

四、配制

基本配制

R1:

interface Serial1/1

ip address 10.1.1.2 255.255.255.0

no sh

!

ip route 20.1.1.0 255.255.255.0 10.1.1.1

R2:

access-list 100 permit ip 10.1.1.0 0.0.0.255 20.1.1.0 0.0.0.255

16000为带宽限制，2000为BC，3000为BE

class-map in-put

match access-group 100

exit

policy-map in-put

class in-put

   police 16000 2000 3000 conform-action set-dscp-transmit 20 exceed-action set-dscp-transmit 10

exit

class-map out-put

对于超出的流量做drop

match ip dscp 10

exit

policy-map out-put

class out-put

   police 8000 1500 3000 conform-action transmit exceed-action drop

exit

int s1/0

bandwidth 16

ip address 10.1.1.1 255.255.255.0

clock rate 64000

service-policy input in-put

no sh

!

interface Serial1/1

bandwidth 16

ip address 20.1.1.1 255.255.255.0

clock rate 64000

service-policy output out-put

no sh

!

R3:

interface Serial1/0

ip address 20.1.1.2 255.255.255.0

no sh

!

ip route 10.1.1.0 255.255.255.0 20.1.1.1

!

验证

R1#ping ip

Target IP address: 20.1.1.2

Repeat count [5]: 10

Datagram size [100]: 2000

Timeout in seconds [2]:

Extended commands [n]:

Sweep range of sizes [n]:

Type escape sequence to abort.

Sending 10, 2000-byte ICMP Echos to 20.1.1.2, timeout is 2 seconds:

!.!..!!.!!

Success rate is 60 percent (6/10), round-trip min/avg/max = 204/457/596 ms

R2#show policy-map

  Policy Map out-put

    Class out-put

     police cir 8000 bc 1500 be 3000

       conform-action transmit

       exceed-action drop

  Policy Map in-put

    Class in-put

     police cir 16000 bc 2000 be 3000

       conform-action set-dscp-transmit af22

       exceed-action set-dscp-transmit af11

从show policy-map我们就可以知道，我们先前设置的

police 16000 2000 3000 conform-action set-dscp-transmit 20 exceed-action set-dscp-transmit 10

police 8000 1500 3000 conform-action transmit exceed-action drop

语名的意义  16000是CAR承诺接入速率 其中bc是令牌桶  be是当信令在bc放满后放到be中

R2#show policy-map int s1/0

Serial1/0

    Class-map: in-put (match-all)

      405 packets, 460260 bytes

      5 minute offered rate 1000 bps, drop rate 0 bps

      Match: access-group 100

      police:

          cir 16000 bps, bc 2000 bytes

        conformed 175 packets, 137072 bytes; actions:

          set-dscp-transmit af22

        exceeded 230 packets, 323188 bytes; actions:

          set-dscp-transmit af11

        conformed 1000 bps, exceed 0 bps

    Class-map: class-default (match-any)

      0 packets, 0 bytes

      5 minute offered rate 0 bps, drop rate 0 bps

      Match: any

R2#show policy-map int s1/1

Serial1/1

    Class-map: out-put (match-all)

      165 packets, 231820 bytes

      5 minute offered rate 0 bps, drop rate 0 bps

      Match: ip dscp af11 (10)

      police:

          cir 8000 bps, bc 1500 bytes

        conformed 88 packets, 117892 bytes; actions:

          transmit

        exceeded 77 packets, 113928 bytes; actions:

          drop

        conformed 0 bps, exceed 0 bps

    Class-map: class-default (match-any)

      261 packets, 122786 bytes

      5 minute offered rate 1000 bps, drop rate 0 bps