XK0-005 Question #1243: Real Exam Question with Answer & Explanation

Question

A user is reporting unusual slowness when trying to transfer a large file to an NFS server from a workstation. The administrator runs tracepath and gets the following output: Which of the following BEST describes the issue and a possible solution?

Options

• AThe path MTU is lower than the source MTU. Reduce the source MTU setting.
• BThere is latency at the storage device. Work with the storage team to correct the issue.
• CThere is latency on an intermediate router. Increase the path MTU to compensate.
• DThere are dropped packets at an intermediate router. Work with the network team to correct the

Explanation

tracepath output suggesting a Path MTU Discovery (PMTUD) issue where the source MTU exceeds the path MTU is best resolved by reducing the source's MTU setting.

Common mistakes.

• B. While slowness can be storage-related, tracepath specifically analyzes network path characteristics like MTU and hop-by-hop latency, not storage device performance.
• C. Increasing the path MTU is incorrect because tracepath identifies the maximum possible MTU that can traverse the path; attempting to send larger packets would exacerbate fragmentation or drops, not compensate for latency.
• D. Although dropped packets cause slowness, the specific information from tracepath regarding MTU mismatch indicates a more precise network configuration issue than general packet drops, which is better addressed by adjusting MTU.

Concept tested. Network troubleshooting (Path MTU Discovery with tracepath)

Reference. https://man7.org/linux/man-pages/man8/tracepath.8.html

No community discussion yet for this question.