LINUX · Text tools · 8 min

Summarize log levels

Combine field selection, sorting, and counting.

Not completed

Your task

Create levels.txt with a count for each first-column log level. Keep events.log unchanged.

What you’re aiming for

ERROR has count 2, INFO has count 3, and WARN has count 1.
The original six events remain.

1. Prepare your practice folder

Use a Linux terminal, such as Ubuntu or WSL on Windows. These examples use Linux file permissions. In WSL, create your practice folder in your Linux home directory (~).

Create a new, empty folder for this exercise. If that name already exists, choose another new name. Continue only after you’re inside the new folder.

NEW PRACTICE FOLDER

mkdir opsrung-linux-count-log-levels && cd opsrung-linux-count-log-levels

Run these setup commands in that folder:

SETUP — RUN ONCE

printf '%s\n' 'INFO ready
ERROR disk
INFO request
WARN retry
ERROR denied
INFO done' > events.log

2. Try the task

Work toward the goal above. Start by inspecting the files or resources, then use a hint if you need one.

Hint 1

awk can print the first whitespace-separated field.

Hint 2

uniq -c counts adjacent repeated lines, so sort first.

Hint 3

Use awk, sort, and uniq -c as a pipeline.

3. Review your result

Use these commands to look at your result and compare it with the goals. The website does not run or verify them.

REVIEW IN YOUR TERMINAL

cat levels.txt
wc -l events.log

What you should see

ERROR has count 2, INFO has count 3, and WARN has count 1.
The original six events remain.

If your result differs: Compare the actual output with each goal. Keep your work inside this exercise’s folder and use only its named resources.

Compare with one possible solution

ONE POSSIBLE SOLUTION

awk '{print $1}' events.log | sort | uniq -c > levels.txt

Other approaches are fine if you reach the same goal. Opening this solution does not mark the exercise complete.

Finished this exercise?

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