一、实验拓扑:
二、实验要求:
1、SW1、SW2、SW3连接后,查看VLAN10的阻塞端口;
2、断开上行链路后,查看阻塞端口NDP需要多长时间变为根端口RP,并进入:Fwarding状态?
3、在该交换机下部署Uplinkfast命令,再次查看需要多长时间进入:Fwarding?
三、命令部署:
1、创建VLAN10
SW1#vlan database
SW1(vlan)#vlan 10
2、将接口变为Trunk、封装dot1q SW1(config)#int range f0/0 - 1 SW1(config-if-range)#switchport trunk encapsulation dot1q SW1(config-if-range)#switchport mode trunk 同理:SW2、SW3同样配置
3、SW3的f0/0接口shutdown,验证是否需要30S f0/1接口才能起来: SW3(config)#int f0/0 SW3(config-if)#shutdown
4、SW3交换机上部署Uplinkfast,验证f0/1接口是否可以秒变Fwarding: SW3(config)#spanning-tree uplinkfast
5、部署Debug命令: SW3#debug spanning-tree uplinkfast Spanning Tree uplinkfast debugging is on
SW3(config)#no spanning-tree uplinkfast SW3(config)# *Mar 1 00:15:26.515: STP FAST: uplinkfast disabled
四、验证: 1、未部署命令前: SW3#show spanning-tree vlan 10 brief Name Port ID Prio Cost Sts Cost Bridge ID Port ID
FastEthernet0/0 128.1 128 19 FWD 0 32768 cc11.9464.0001 128.1
FastEthernet0/1 128.2 128 19 BLK 19 32768 cc12.9464.0001 128.2
2、SW3的f0/0接口shutdown后,f0/1需要30s进入Fwarding状态: SW3#show spanning-tree vlan 10 brief Name Port ID Prio Cost Sts Cost Bridge ID Port ID
FastEthernet0/1 128.2 128 19 LIS 19 32768 cc12.9464.0001 128.2
SW3#show spanning-tree vlan 10 brief Name Port ID Prio Cost Sts Cost Bridge ID Port ID
FastEthernet0/1 128.2 128 19 LRN 19 32768 cc12.9464.0001 128.2
SW3#show spanning-tree vlan 10 brief Name Port ID Prio Cost Sts Cost Bridge ID Port ID
FastEthernet0/1 128.2 128 19 FWD 19 32768 cc12.9464.0001 128.2
3、SW3交换机上部署Uplinkfast:
SW3#show spanning-tree vlan 10 brief
Name Port ID Prio Cost Sts Cost Bridge ID Port ID
FastEthernet0/1 128.2 128 3019 FWD 19 32768 cc12.9464.0001 128.2