Question 19
UnclassifiedA network admin changed the subnet manager configuration and you need to verify that all paths through the fat-tree topology are balanced and that no credit loops exist in the new routing.
Correct answer: C
Explanation
ibdiagnet is the InfiniBand diagnostic utility used to analyze fabric topology and routing. It checks that paths in a fat-tree are balanced and helps detect routing problems such as credit loops after subnet manager changes.
Why each option is right or wrong
A. ibstat
B. perfquery
C. ibdiagnet
The InfiniBand diagnostic utility defined for fabric-wide validation is `ibdiagnet`, which is used after subnet manager changes to inspect topology and routing consistency across the subnet. In a fat-tree, it can verify that all end-to-end paths remain balanced and flag routing anomalies such as credit loops, making it the appropriate post-change check for the new configuration.
D. iblinkinfo