单项选择题
What is the function of the helper router during a restart event in OSPF?（）
A. Sends Rapid Hellos to the restarting router. B. Maintains Adjancency with restarting router. C. Sends periodic DD packets to the restarting router. D. Floods Type 9 LSAs to all routers indicating a restarting event.
问答题 Click the Task button. Place the CoS processing steps in the correct sequence.
多项选择题 Which two steps are needed when configuring multiple RPs using MSDP within a single PIM domain? （）
多项选择题 What are two commands that can be used to configure MBGP for multicast?（）
