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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
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
