350-401 Question 390
Select 3A network engineer is configuring a BGP session between two routers to exchange both IPv4 and IPv6 routes. The engineer needs to ensure that the address families are appropriately supported and advertised during the BGP negotiation. What configurations must be applied to enable this functionality?
- A
Enable the 'neighbor
activate' command under both IPv4 and IPv6 address families. - B
Configure the 'neighbor
address-family ipv6 unicast' command to support IPv6 routes. - C
Use the 'neighbor
advertise ipv4 unicast' command to explicitly advertise IPv4 routes. - D
Ensure the 'neighbor
remote-as' command is configured to establish the BGP session. - E
Configure the 'bgp log-neighbor-changes' command to monitor BGP neighbor state transitions.
Show answer and explanation
Correct answers: A, B, D
Explanation
To exchange both IPv4 and IPv6 routes in a BGP session, the address families for IPv4 and IPv6 unicast must be explicitly activated using the 'neighbor
- A. Correct.
The 'neighbor
activate' command is necessary to activate the address family for the BGP session. This must be done for both IPv4 and IPv6 address families. - B. Correct.
The 'address-family ipv6 unicast' command is required to activate IPv6 route exchange using BGP.
- C. Incorrect.
The 'neighbor
advertise ipv4 unicast' command is not valid in BGP configuration syntax. IPv4 routes are advertised automatically once the IPv4 address family is activated. - D. Correct.
The 'neighbor
remote-as' command is mandatory to establish a BGP session with the neighbor by specifying its AS number. - E. Incorrect.
The 'bgp log-neighbor-changes' command is optional and only provides logging for state changes; it does not directly enable address families or route exchange.