一个Trunk的问题

babl

问题如下：

The network administrator is trying to add Switch1 to the network,but the 802.1Q trunk is not coming up.Switch1 was previously tested in the laboratory and its trunk configuration worked fine. What are three possible causes of this problem ?(choose Three)

A.There is a VTP domain name mismatch

B.The trunking configuration mode on the other end is set to Desirable

C.Cisco Discovery Protocol is not running on the other end.

D.Switch1 does not support 802.1Q.

E.The trunking configuration mode on Switch1 is set to Off.

F.The trunking configuration mode on the other end is set to On.

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我选择的答案是：A、D、E。但是给出来的正确答案是：A、B、F。 请各位大哥帮忙分析下A、B、F是否正确的答案？如果是，为啥B跟F是正确的？ 谢谢各位！

tablesnow

我认为根据题设条件你不知道对端的SW的封装，所以要强起Trunk ,对端SW的mode应为Trunk.