JNCIS-ENT: Juniper Networks Certified Specialist – Enterprise Routing and Switching (2024) — Question 33

Your network connections to the Internet through two different ISPs using EBGP. You must ensure that ISP1 is the primary path used for all traffic entering your network while using ISP2 as a backup path.
In this scenario, which statement is correct?

Answer options

• A. You should use a lower MED value on routes sent to ISP1.
• B. You should assign a higher local preference on routes that you are sending to ISP1.
• C. You should change the next hop for all routers sent to ISP2.
• D. You should prepend your local AS number three times on routes that you are sending to ISP2.

Correct answer: D

Explanation

The correct answer is D because prepending your AS number multiple times on routes to ISP2 makes those routes less preferred compared to ISP1, thus ensuring that ISP1 is the primary path. Option A is incorrect as a lower MED value actually increases preference, while B is wrong because routes to ISP1 should have a higher local preference, not ISP2. Option C is not relevant to establishing preference between ISPs.