Essay As shown in the figure, R3 is deployed at the border of an enterprise's campus network. R3 is connected to the Internet through links of two different operators: ISP1 and ISP2. Because the link of ISP1 provides a higher bandwidth, the administrator requires that all traffic be preferentially transmitted to the Internet through the link of ISP1 and that the link of ISP2 be used as a backup link. (1) Describe the functions that need to be deployed on R3 to meet the preceding requirements. (5 points) (2) If all system control and management boards of R1 can not work properly but other boards are working properly, how could R3 switch the Internet access traffic to the link of ISP2? Provide at least two solutions (assuming that no dynamic routing protocol is deployed between R3 and R1). (5 points)
Solution: 95% score (1) If the BGP protocol is running between R3 and ISP: configure the route-policy of incoming and receiving routes for ISP1 and ISP2 on R3 and set the local preference attribute. When receiving routes from ISP1, the local preference value is 200, and when receiving routes from ISP2, it is local The priority value is the default 100. If static routing is running between R3 and ISP: configure two default routes on R3 to point to ISP1 and ISP2, and set different priorities at the same time ip route-static 0.0.0.0 0.0.0.0 10.1.1.2 //ISP1 ip route-static 0.0.0.0 0.0.0.0 20.1.1.2 preference 100 //ISP2 (2) solution1:BFD FOR static R3: bfd bfd a bind peer-ip 10.1.1.2 //ISP1 discriminator local 1 discriminator remote 2 min-tx-interval 10 commit ip route-static 0.0.0.0 0.0.0.0 10.1.1.2 track bfd-session a //ISP1 ip route-static 0.0.0.0 0.0.0.0 20.1.1.2 preference 100 //ISP2 solution2:NQA(Network Quality Analyzer) NQA works with Track and application modules to monitor changes in network status in real time and send test packets
|