1 适用型号
N9500-R系列交换机
N7700系列交换机
N5600系列交换机
N3100-V系列交换机
2 交换机配置
2.1 配置流程：
1. 创建ACL匹配目标流量
2. 创建class-map，用于policy-map与ACL进行关联，policy-map无法直接调用ACL
3. 创建policy-map，关联class-map并设置相关参数
4. 在物理接口或聚合口下调用
2.2 配置示例
2.2.1 N9500-R&N3100-V配置
ip access-list dn-limit-acl
10 permit ip 192.168.1.0 0.0.0.255 any
ip access-list mgmt-limit-acl
10 permit ip 192.168.0.0 0.0.0.255 any
ip access-list yw-limit-acl
10 permit ip 192.168.2.0 0.0.0.255 any
class-map type qos match-all dn-limit-class
match access-group name dn-limit-acl
class-map type qos match-all yw-limit-class
match access-group name yw—limit-acl
class-map type qos match-all mgmt-limit-class
match access-group name mgmt-limit-acl
policy-map type qos qos-limit-speed
class mgmt-limit-class
police cir percent 20 bc 200 ms conform transmit violate drop
class dn-limit-class
police cir percent 30 bc 200 ms conform transmit violate drop
class yw-limit-class
police cir percent 50 bc 200 ms conform transmit violate drop
interface e1/1
service-policy type qos input qos-limit-speed
2.2.2 N56配置
ip access-list dn-acl
statistics per-entry
10 permit ip 192.168.2.0/24 any
ip access-list dw-acl
statistics per-entry
10 permit ip 192.168.1.0/24 any
ip access-list yw-acl
statistics per-entry
10 permit ip 192.168.3.0/24 any
class-map type qos match-all dn-class
match access-group name dn-acl
class-map type qos match-all dw-class
match access-group name dw-acl
class-map type qos match-all yw-class
match access-group name yw-acl
policy-map type qos qos-limit
class dn-class
police cir percent 20 bc 200 ms conform transmit violate drop
set qos-group 1
class dw-class
police cir percent 30 bc 200 ms conform transmit violate drop
set qos-group 1
class yw-class
police cir percent 50 bc 200 ms conform transmit violate drop
set qos-group 1
interface e1/1
service-policy type qos input qos-limit
2.2.3 N77配置
ip access-list dn-acl
10 permit ip 192.168.2.0/24 any
ip access-list mgmt-acl
10 permit ip 192.168.1.0/24 any
ip access-list yw-acl
10 permit ip 192.168.3.0/24 any
class-map type qos match-all dn-class
match access-group name dn-acl
class-map type qos match-all yw-class
match access-group name yw-acl
class-map type qos match-all mgmt-class
match access-group name mgmt-acl
policy-map type qos speed-limit
class mgmt-class
police cir percent 20 bc 200 ms conform transmit violate drop
class dn-class
police cir percent 30 bc 200 ms conform transmit violate drop
class yw-class
police cir percent 50 bc 200 ms conform transmit violate drop
interface e1/1
service-policy type qos input speed-limit
2.2.4 特殊配置说明
2.2.4.1 N56
CN8K中默认存在一个名为class-default的class，该class默认匹配所有有流量，并将流量划分到qos-group 0 当中，该默认配置不能被删除，被修改
通过在policy当中将创建的class设置为qos-group 1可绕开该默认设备；
2.2.4.2 N3100-V
N3100-V由于硬件限制，将policy-map调用到接口下时，会报错，提示没有该资源，需要通过手动分配硬件资源并重启，才能正常调用；命令如下：
Switch(config)#hardware access-list tcam region qos 256
2.2.4.3 默认参数
在policy-map中为class分配带宽资源时，默认会设置BC（突发流量）为200ms；该配置可进行相关修改，可选范围为1-536870912，可选单位为：bytes/kbytes/mbytes/ms/us/packets
3 流量仪打流结果
3.1 N77测试结果
3.1.1 固定报文长度测试结果
3.1.2 随机报文长度测试结果
3.2 N56测试结果
3.2.1 固定报文长度测试结果
3.2.2 随机报文长度测试结果
3.3 N3100-V测试结果
3.3.1 固定报文长度测试结果
3.3.2 随机报文长度测试结果
4 测试结论：
在Nexus交换机上，可以针对匹配特定流量进行相关带宽分配，并可设置允许突发流量通过。以此实现更高需求；
根据打流测试结果发现，当数据包长度越大时，带宽分配效果越好；现实组网中的混合数据包长度，带宽分配效果达到预期；
