Click the Exhibit button. The exhibit shows a 15454/15216 DWDM system and alarm indications. What are two possible sources of trouble shown in the system？（）
請(qǐng)參見(jiàn)圖示。交換機(jī)均為默認(rèn)配置。主機(jī) A 需要與主機(jī) D 通信，但主機(jī) A 沒(méi)有其默認(rèn)網(wǎng)關(guān)的 MAC 地址。哪些網(wǎng)絡(luò)主機(jī)將收到主機(jī) A 發(fā)送的 ARP 請(qǐng)求（）
Refer to the exhibit. LACP has been configured on Switch1 as shown. Which is the correct command set to configure LACP on Switch2？（）
Refer to the exhibit， which shows a PPPoA diagram and partial SOHO77 configuration. Which command needs to be applied to the SOHO77 to complete the configuration？（）
Refer to the exhibit. Look at the command output. What can you use to prevent this behavior？（）
