简单介绍portfast属性.
简单介绍portfast属性.
相关考题：
在J2EE中,javaBeans规范允许四种类型的属性,它们是()。 A.简单属性，关联属性，受限属性，定制属性B.简单属性，内省属性，持续化属性，索引属性C.简单属性，内省属性，事件属性，定制属性D.简单属性，绑定属性，限制属性，索引属性
（ 20 ）提高 Catalyst 6500 发生间接链路失效的收敛速度，正确配置 STP 可选功能的命令是A ） set spantree backbonefast enableB ） set spantree uplinkfast enableC ） set spantree portfast 3/2 enableD ） set spantree portfast bpdu-filter enable
Which spanning-tree command would cause a PortFast-enabled interface to lose its PortFast-operational status and disable BPDU filtering if it receives BPDUs？（）A、spanning-tree guard rootB、spanning-tree portfast bpduguard defaultC、spanning-tree bpduguard enableD、spanning-tree bpdufilter enableE、spanning-tree portfast bpdufilter default
Which two statements correctly describe characteristics of the PortFast feature？ （）A、STP will be disabled on the port.B、PortFast can also be configured on trunk ports.C、PortFast is required to enable port-based BPDU guard.D、PortFast is used for both STP and RSTP host ports.E、PortFast is used for STP-only host ports.
在J2EE中，javaBeans规范允许四种类型的属性，它们是（）。 A、简单属性，关联属性，受限属性，定制属性B、简单属性，内省属性，持续化属性，索引属性C、简单属性，内省属性，事件属性，定制属性D、简单属性，绑定属性，限制属性，索引属性
The following was configured on a switch： Switch（config） # spanning-tree portfast bpdufilter default What is the effect of this configuration command？（）A、If BPDUs are received by a port configured for PortFast， they are ignored and none are sent.B、The command will enable BPDU filtering on all ports regardless of whether they are configured for BPDU filtering at the interface level.C、If BPDUs are received by a port configured for Portfast， the port will transition to forwarding state.D、If BPDUs are received by a port configured for PortFast， then PortFast is disabled and the BPDUs are processed normally.E、None of the other alternatives apply.
Prior to 802.1w，Cisco implemented a number of proprietary enhancements to 802.1D to improve convergence in a Layer 2 network. Which statement is correct？（）A、Only UplinkFast and BackboneFast are specified in 802.1w；PortFast must be manually configured.B、Only PortFast is specified in 802.1w；UplinkFast and BackboneFast must be manually configured.C、None of the proprietary Cisco enhancements are specified in 802.1w.D、PortFast，UplinkFast，and BackboneFast are specified in 802.1w.
问答题what is portfast？