switchport trunk native vlan 999 这个命令起什么作用？（）

A . A．顺风顺流 B . B．顶风顶流 C . C．顺风顶流 D . D．顶风顺流

A . 创建vlan20的接口 B . 指定vlan20的流量不能被打标记 C . 阻止vlan20的流量在干道通过 D . 所有未打标记的流量都默认指定为vlan20

A . A、VL＞1.0-1.6 B . B、VL＞1.6-2.5 C . C、VL≤1.0

A . 当需要保护未使用的交换机端口时 B . 当只允许一台主机设备连接到端口时 C . 当想使端口识别MAC地址表中静态分配的MAC地址时 D . 当多台设备共用同一端口时

A . A dynamically learned MAC address is saved in the startup-configuration file. B . A dynamically learned MAC address is saved in the running-configuration file. C . A dynamically learned MAC address is saved in the VLAN database. D . Statically configured MAC addresses are saved in the startup-configuration file if frames from that address are received. E . Statically configured MAC addresses are saved in the running-configuration file if frames from that address are received.

A . A．顺风顺流 B . B．顶风顶流 C . C．顺风顶流 D . D．顶风顺流

A . show interfaces interface B . show vlan brief C . show interfaces interface switchport D . show interface interface trunk E . show interfaces vla

A . ①③②④ B . ①②③④ C . ①②④③ D . ①④②③

A . Incorrect VTP domain B . Incorrect VTP password C . Incorrect VTP mode D . Incorrect VTP configuration revisio

A . enables PortFast B . disables trunking C . disables Cisco Discovery Protocol D . enables port security E . enables loopguard F . disables EtherChannel

A . show interfaces interface B . show vlan bri C . show interfaces interface switchport D . show interface interface trunk E . show interfaces vla

A . 将该端口关闭 B . 将该端口配置为二层交换端口 C . 将该端口配置为三层路由端口 D . 将该端口配置为Trunk端口

A . The port is configured for both data and voice traffic. B . The port is fully dedicated to forwarding voice traffic. C . The port will operate as an FXS telephony port. D . Voice traffic will be redirected to VLAN 222.

A . It creates a VLAN 999 interface. B . It designates VLAN 999 for untagged traffic. C . It blocks VLAN 999 traffic from passing on the trunk. D . It designates VLAN 999 as the default for all unknown tagged traffic.

A . 由于本征VLAN不是默认VLAN，DTP将无法协商中继链路。 B . 除非相连的远程接口也配置为动态期望模式，否则该接口无法协商中继链路 C . 相连的设备会动态确定必须通过该链路传输多个VLAN的数据的时机并根据需要打开中继链路。 D . 如果使用switchport mode dynamic auto命令或switc hportmode trunk命令配置远程相连设备，则会形成中继链路

A . A dynamically learned MAC address is saved in the startup-configuration file. B . A dynamically learned MAC address is saved in the running-configuration file. C . A dynamically learned MAC address is saved in the VLAN database. D . Statically configured MAC addresses are saved in the startup-configuration file if frames from that address are received. E . Statically configured MAC addresses are saved in the running-configuration file if frames from that address are received.

A . Incorrect VTP domain B . Incorrect VTP password C . Incorrect VTP mode D . Incorrect VTP configuration revisio

A . By default， native VLAN packets going out this port will be tagged. B . Without an encapsulation command， 802.1Q will be the default encapsulation if DTP fails to negotiate a trunking protocol. C . The interface will support the reception of tagged and untagged traffic. D . If the device connected to this port is not 802.1Q-enabled， it will not be able to handle 802.1Q packets.

A .  Causes the interface to apply ISL framing for traffic on VLAN 7 B .  Configures the trunking interface to forward traffic from VLAN 7 C .  Configures the interface to be a trunking port and causes traffic on VLAN 7 to be 802.1q tagged D .  Configures the trunking interface to send traffic from VLAN 7 untagged E .  None of the other alternatives apply

A．POS链路 B．2M链路 C．GE链路 D．ATM