System logs (/var/log) in Linux CLI - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the command to view the last 10 lines of the system log file /var/log/syslog.

Linux CLI

tail [1] 10 /var/log/syslog

Drag options to blanks, or click blank then click option'

A-f

B-r

C-n

D-c

Attempts:

3 left

💡 Hint

Common Mistakes

Using -f instead of -n which follows the file continuously.

Using -r which reverses the output order.

Using -c which shows bytes instead of lines.

The tail -n 10 shows the last 10 lines from the end of the file.

2fill in blank

medium

Complete the command to search for the word error in the /var/log/auth.log file, ignoring case.

Linux CLI

grep [1] error /var/log/auth.log

Drag options to blanks, or click blank then click option'

A-i

B-v

C-c

D-n

Attempts:

3 left

💡 Hint

Common Mistakes

Using -v which inverts the match.

Using -c which counts matches instead of showing them.

Using -n which shows line numbers but does not ignore case.

The -i option makes grep ignore case, so it finds 'error', 'Error', or 'ERROR'.

3fill in blank

hard

Fix the error in the command to continuously monitor the /var/log/kern.log file for new entries.

Linux CLI

tail [1] /var/log/kern.log

Drag options to blanks, or click blank then click option'

A-f

B-n 20

C-r

D-c 100

Attempts:

3 left

💡 Hint

Common Mistakes

Using -n 20 which only shows last 20 lines once.

Using -r which reverses the output order.

Using -c 100 which shows bytes, not lines.

The -f option makes tail follow the file and show new lines as they are added.

4fill in blank

hard

Fill both blanks to create a command that counts how many times the word failed appears in /var/log/auth.log.

Linux CLI

grep [1] failed /var/log/auth.log | wc [2]

Drag options to blanks, or click blank then click option'

A-i

B-l

D-c

Attempts:

3 left

💡 Hint

Common Mistakes

Using grep -l which lists filenames, not matches.

Using wc -c which counts bytes, not lines.

Use grep -i to find 'failed' ignoring case, then wc -l to count the matching lines.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension in Python that maps each log filename in logs to its size in bytes, but only if the size is greater than 1000.

Linux CLI

sizes = { [1]: os.path.getsize([2]) for [3] in logs if os.path.getsize([2]) > 1000}

Drag options to blanks, or click blank then click option'

Alog

Dfilename

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names inconsistently.

Using a variable not defined in the loop.

Use the variable log as the key and value source in the comprehension. It represents each filename in the logs list.