Exam 300-410 topic 1 question 75 discussion

You must use the transit area not the back-bone area, therefore B and C are incorrect..

AE Reference: https://www.cisco.com/c/en/us/support/docs/ip/open-shortest-path-first-ospf/13703-8.html An important thing to remember when configuring virtual-link is we need to configure the OSPF router ID and NOT the IP address of the ABR. Therefore in this question we have to use the command “area 234 virtual-link 0.0.0.44” on R2 and “area 234 virtual-link 0.0.0.22” on R4.

Question is wrong, the options are not like that in the exam.

A & E, check this https://networklessons.com/ospf/how-to-configure-ospf-virtual-link

For those, who see a virtual-link configuration with the router-id for the first time, like me: https://www.cisco.com/c/en/us/support/docs/ip/open-shortest-path-first-ospf/13703-8.html

Why not AD? R2 would be looking for the 0.0.0.44, what would be the ID of R4 and R4 would be looking for 10.23.23.2, what would be the ID of R2. Am I missing something?

The only error in the provided config is that were using the interface address instead of the router id

AE is correct because each router points to the router ID of the other router.

AE are correct. BC are incorrect. The virtual link will use the transit area (area 234) to reach back to area 0 via router 0.0.0.22

https://www.cisco.com/c/en/us/support/docs/ip/open-shortest-path-first-ospf/8313-27.html

The correct answer is: AE

A & E are wrong answers B & C are the right answers as they use area 0 for virtual links to work