cisco 640 802 ccna portable command guide 2008 phần 8

Thay đổi bộ đếm thời gian hello-trì hoãn đến 4 giây trên VLAN 5 Thay đổi bộ đếm thời gian chuyển tiếp, chậm trễ đến 20 giây trên VLAN 5 Thay đổi bộ đếm thời gian tối đa lão hóa đến 25 giây trên VLAN 5Chú ý: Đối với các lệnh thời gian hello-, phạm vi từ 1 đến 10 giây. | Spanning Tree Protocol 143 Configuring STP Timers Switch config spanning-tree vlan 5 hello-time 4 Changes the hello-delay timer to 4 seconds on VLAN 5 Switch config spanning-tree vlan 5 forward-time 20 Changes the forward-delay timer to 20 seconds on VLAN 5 Switch config spanning-tree vlan 5 max-age 25 Changes the maximum-aging timer to 25 seconds on VLAN 5 NOTE For the hello-time command the range is 1 to 10 seconds. The default is 2 seconds. For the forward-time command the range is 4 to 30 seconds. The default is 15 seconds. For the max-age command the range is 6 to 40 seconds. The default is 20 seconds. CAUTION Cisco recommends caution when using this command. Cisco further recommends that the spanning-tree vlan x root primary or the spanning-tree vlan xroot secondary command be used instead to modify the switch timers. Verifying STP Switch show spanning-tree Displays STP information Switch show spanning-tree active Displays STP information on active interfaces only Switch show spanning-tree brief Displays a brief status of the STP Switch show spanning-tree detail Displays a detailed summary of interface information Switch show spanning-tree interface gigabitethernet 0 1 Displays STP information for interface gigabitethernet 0 1 Switch show spanning-tree summary Displays a summary of port states Switch show spanning-tree summary totals Displays the total lines of the STP section Switch show spanning-tree vlan 5 Displays STP information for VLAN 5 144 Spann ing Tree Protocol Optional STP Configurations Although the following commands are not mandatory for STP to work you might find these helpful to fine-tune your network. PortFast Switch config interface fastethernet 0 10 Moves to interface configuration mode. Switch config-if spanning-tree portfast Enables PortFast on an access port. Switch config-if spanning- tree portfast trunk Enables PortFast on a trunk port. WARNING Use the portfast command only when connecting a single end station to an access or trunk .