Refer to the exhibit. The network administrator configured the network to connect two disjointed networks and all the connectivity is up except the virtual link, which causes area 250 to be unreachable.
Which two configurations resolve this issue? (Choose two.)
To establish a virtual link in OSPF, you need to correctly configure the virtual link by specifying the router ID of the remote ABR through the transit area. The correct configurations on R2 and R4 should point to the router ID of the opposite router using the transit area. Therefore, configuring R2 with 'no area 234 virtual-link 10.34.34.4' and 'area 234 virtual-link 0.0.0.44' (router ID of R4), and configuring R4 with 'no area 234 virtual-link 10.23.23.2' and 'area 234 virtual-link 0.0.0.22' (router ID of R2) resolves the issue.
https://www.cisco.com/c/en/us/support/docs/ip/open-shortest-path-first-ospf/8313-27.html
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
A & E are wrong answers B & C are the right answers as they use area 0 for virtual links to work
In the configuration of Virtual Links, we use the area of the trasnsit, not the backbone area. So A and E are correct.
The correct answer is: AE
AE is correct because each router points to the router ID of the other router.
The only error in the provided config is that were using the interface address instead of the router id
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
Sorry, it was some misunderstanding by me, virtual-link is always configured with the OSPF router ID of the other ABR, and not the IP. https://networklessons.com/ospf/how-to-configure-ospf-virtual-link
A & E, check this https://networklessons.com/ospf/how-to-configure-ospf-virtual-link
You must use the transit area not the back-bone area, therefore B and C are incorrect..
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?
Question is wrong, the options are not like that in the exam.
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.
A & E are correct