A manufacturer fails over to the backup circuit, and only the tests that use that circuit show loss. Where is the fault?
Select an answer to reveal the explanation.
Short Explanation
If only the spare bridge is crumbling, you fix that bridge instead of rebuilding the factory. You put the fault on the backup path because loss shows up only when tests ride that circuit. The browser, DNS, and the plant wireless are the wrong places for evidence that follows the backup circuit.
Full Explanation
Tests that stay on the primary circuit do not show the loss, and tests that move to the backup circuit do. The fault follows the backup path, so that circuit is where the investigation belongs. On the backup path that is the only circuit showing loss is where the failover comparison places the fault. A problem in the browser that renders the plant dashboard for operators would follow the client, not the circuit the test took. Operators would see a browser fault whether or not the plant had failed over. A problem in DNS only, even though the loss follows the backup circuit, would break name lookup independent of which circuit is in use. It would not isolate itself to the backup path the tests just switched onto. A problem on the plant wireless network, which these circuit tests do not use, is off the path the evidence describes. The loss appears when the backup circuit is in use, which is a path finding. Exam caveat: when a symptom appears only after failover, compare the two paths before you chase a client, a name lookup, or a wireless segment. Operational check: run the same test on the primary and on the backup and confirm the loss is confined to the backup path, then inspect the hop on that path where the loss begins.