Disk space monitoring script in Bash Scripting - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

Disk usage percentage extraction

What is the output of this command snippet that extracts disk usage percentage for root (/) partition?

Bash Scripting

df / | tail -1 | awk '{print $5}'

A 85

B 85%

C /dev/sda1

D Filesystem

💡 Hint

Look at the fifth column of the df output for root partition.

The df command shows disk usage. The fifth column is the percentage used, including the percent sign.

❓ Configuration

intermediate

Cron job for disk space alert

Which cron job entry runs a disk space check script every day at 6 AM?

A 0 6 * * 1 /usr/local/bin/disk_check.sh

B 0 18 * * * /usr/local/bin/disk_check.sh

C 0 6 * * * /usr/local/bin/disk_check.sh

D 6 0 * * * /usr/local/bin/disk_check.sh

💡 Hint

Cron format is: minute hour day month weekday

The entry '0 6 * * *' means at minute 0, hour 6, every day, every month, every weekday.

❓ Troubleshoot

advanced

Script fails to send alert email

A disk space monitoring script uses 'mail' command to send alerts but no emails are received. What is the most likely cause?

A The mail command is not installed or configured properly on the system.

B The disk usage threshold is set too high in the script.

C The script does not have execute permission.

D The disk partition is mounted read-only.

💡 Hint

Check if the mail command works independently.

If mail is not installed or configured, the script cannot send emails even if triggered.

🔀 Workflow

advanced

Disk space alert workflow

Which sequence correctly describes a disk space alert workflow?

A 1,2,3,4

B 2,1,3,4

C 1,3,2,4

D 3,1,2,4

💡 Hint

Think about the logical order of checking, comparing, alerting, then logging.

First check usage, then compare to threshold, then alert if needed, finally log the event.

✅ Best Practice

expert

Efficient disk space monitoring script design

Which practice improves efficiency and reliability of a disk space monitoring script?

A Send alert emails every minute regardless of disk usage changes

B Run multiple df commands separately for each partition to isolate errors

C Hardcode disk usage thresholds inside the script without external config

D Use a single df command with parsing to check all relevant partitions at once

💡 Hint

Minimize system calls and centralize configuration for maintainability.

Using one df command reduces overhead and parsing all partitions at once is efficient and reliable.