Which two statements about eBGP neighbor relationships are true? (Choose two.)
Click on the arrows to vote for the correct answerA. B. C. D. E.
The correct answers are A and B.
External Border Gateway Protocol (eBGP) is used to exchange routing information between routers in different autonomous systems (AS). Here are the explanations for each option:
A. The two devices must reside in different autonomous systems: This statement is true for eBGP. As per BGP protocol, routers running eBGP must reside in different autonomous systems.
B. Neighbors must be specifically declared in the configuration of each device: This statement is also true for eBGP. To establish an eBGP neighbor relationship, the neighbor IP address must be explicitly configured on each router.
C. They can be created dynamically after the network statement is configured: This statement is false. In BGP, network statements are used to identify the networks that will be advertised to BGP peers, but they do not create neighbor relationships.
D. The two devices must reside in the same autonomous system: This statement is false for eBGP, as mentioned earlier. Routers running eBGP must reside in different autonomous systems.
E. The two devices must have matching timer settings: This statement is false. Although BGP uses timers to manage neighbor relationships, the timer settings do not need to match between neighbors. By default, the BGP keepalive timer is set to 60 seconds and the hold timer is set to 180 seconds. If one router sends keepalive messages but does not receive a response from its neighbor within the hold time, the neighbor relationship is terminated.
In summary, eBGP neighbors must be explicitly configured on each router and reside in different autonomous systems.