[R1]ospf 1
[R1-ospf-1]area 2
[R1-ospf-1-area-0.0.0 2] network 10.0.13.1 0.0.0.0
As shown in the configuration, the administrator has configured OSPF on R1, but R1 cannot learn the routes of other routers, so the possible reason is ().

• A. This router does not have an OSPF process ID configured
• B. This router's advertised network address does not match the interface mask
• C. The area ID configured by this router and the area I of its neighbor routersD is different
• D. This router is not configured with the authentication function, but the neighbor router is configured with the authentication function

The following is about cross-domain VPN-Option The characteristics of C, the description is correct?

• A. A maximum of two layers of labels are required during packet forwarding.
• B. The ASBRs do not store VPNv4 routes, nor do they advertise VPNv4 routes to each other.
• C. Cross-domain VPN-Option The C method is not suitable for use when spanning multiple ASs.
• D. VPN routes are directly exchanged between ingress PEs and egress PEs, without the need for intermediate devices to store and advertise VPN routes.

The switches SWA and SWB are connected through two Ethernet links, and the switch SWA has the following interface configurations:

• A. Because of the VLA allowed to passN is different, GigabitEthemet1/0/1 Cannot join the same aggregation group as GigabitEthernet1/0/2
• B. Only the GigabitEtheThe configuration of rmet1/0/2 is changed to be the same as that of GigabitEthemet1/0/1, so that the two can join the same aggregation group
• C. After link aggregation is configured on both SWA and SWB, if the switches SWA and SWBopen Kai MSTP, then GigabitEthernet1/0/1 and GigabitEthernet1/0/2 are in the forwarding state of MSTP
• D. No need to change the current configuration, GigabitEthemnet1/0/1 and GigabitEthernet1/0/2 can join the same aggregation group

Which scenarios can use AS-path-filter?

• A. A carried by routeSPATH attribute to filter routes received from BGP neighbors. For example the command peer xxxx as-path-fliter import
• B. A carried by routeSPATH attribute to filter routes sent to BGP neighbors. For example the command peer xxxx as-path-ilter export
• C. if-match clause in Route-policy
• D. Route apply clause in policy

The OSPF protocol runs on a company's network. An engineer performs packet diversion operations on the network in order to gain a deeper understanding of the OSPF mechanism. Which of the following descriptions about OSPF packets is correct?

• A. After receiving the LsUpdate message, the router must send LsAck to confirm
• B. LS Update packets synchronize the link state database by sending detailed LSA information
• C. LSUpdate packets are only sent when adjacency is established
• D. Add interface to OSPSend Hello message immediately after area F