Free Access Cisco 300-410 New Release

In the configuration above, the engineer has made a mistake as he was tracking 172.16.35.6 (the backup path) instead of tracking the main path (172.16.35.2). Therefore,when he shut down the main path, the track 1 was still up so traffic still went through the main path -> it failed.

To fix this issue, we just need to correct the tracking interface of the main path.

From the output, we learned that R1 was trying to establish BGP neighbor relationship with R3 but failed. Both of them were using physical interface to establish neighbor relationship so wedon’t need the “… ebgp-multihop” command here. The only reasonable answer is R3 has not been configured to activate BGP neighbor relationship with R1.

The IPv6 Router Advertisement Guard feature provides support for allowing the network administrator to block or reject unwanted or rogue router advertisement guard messages that arrive at the network device platform. Router Advertisements are used by devices to announce themselves on the link. The IPv6 Router Advertisement Guard feature analyzes these router advertisements and filters out router advertisements that are sent by unauthorized devices.

Certain switch platforms can already implement some level of rogue RA filtering by the administrator configuring Access Control Lists (ACLs) that block RA ICMP messages that might be inbound on “user” ports.

When the aggregate-address command is used within BGP routing, the aggregated address is advertised, along with the more specific routes. The exception to this

rule is through the use of the summary-only command. The “summary-only” keyword suppresses the more specific routes and announces only the summarized

route.