performance
hard
Apply
log-pipeline
2 points
Question 26. CSCD240-E1-C
Top 5 source IPs appearing on FAIL lines of auth.log (IP = field 5).
Work the drill
Answer on paper or in a terminal before revealing the ideal answer.
Ideal answer
grep FAIL auth.log | awk '{print $5}' | sort | uniq -c | sort -rn | head -5
Misconception bank
Each row below is a plausible wrong answer, the thinking that produces it, and the remedy that corrects the misconception. These are the foundation of the multiple-choice framing and the targeted feedback a student receives after answering.
awk '{print $5}' auth.log | sort | uniq -c | sort -rn | head -5
Misconception. Missing FAIL filter.
Remedy. Filter first.
grep FAIL auth.log | sort | uniq -c | sort -rn | head -5
Misconception. No field extraction; whole-line dedupe.
Remedy. Extract field first.
Authority mappings
Hover any chip for the mapping justification; click to open the authority record.
DCWF tasks:
T0447
KU outcomes:
CO-M9-O1
NCAE errors:
WWW Content / failure: Failed to connect to hostWWW Content / timeout: TimeoutWWW Content / failure: Website cannot be reachedSSH Login / failure: Failed to connect to host: IPSSH Login / partial: The following users failed t.SSH Login / partial: The following users failed t.
Course-artifact links
Lectures
- CSCD240-S26-L08. Pipes, filters, grep, sort, uniq, wc, tar