The three routers are running IS-IS and have established adjacency relationships. The area numbers and router levels are marked as shown in the figure. If the road between R1 and R2 is interrupted, which of the following statements is correct? (Multiple choice)

For the link state routing protocol, when filter-policy import is used, the filtered link state information cannot be calculated as a route, and its neighbors cannot receive complete link state information.

The content contained in the UPDATE message, which of the description is wrong?

Among the commonly used routing policy tools for BGP, what can be used to filter routes? (Multiple choice)

In the WL AN network, enabled HSB backup group, after the AP has been online on the active AC, then Offline on the standby AC and add the AP information, AP status on the standby AC is Fault. At this time, you need to execute the undo hsb enable command in the HSB backup group view of the standby AC to disable the HSB active/standby backup function, and then execute the hsb enable command to enable the HSB active/standby backup function. At this time, the information on the active AC will be backed up to Standby AC to achieve consistent backup of active and standby information, the AP status on the AC will be displayed as standby.