Linux Shell Backup Project – IBM Data Engineering Professional Certificate

Overview

This project demonstrates the use of Bash scripting to automate file backups based on modification time. It was completed as the final project for Course 6 – Hands-on Introduction to Linux Commands and Shell Scripting in the IBM Data Engineering Professional Certificate.

The project simulates a real-world DevOps or system administration task: creating a shell script (backup.sh) that identifies recently modified files and backs them up into a timestamped archive. The script uses core Linux utilities including tar, date, mv, and file permission commands, and is designed to support automation via cron.

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Objectives

• Create a Bash script that:
  • Accepts source and destination directories as arguments
  • Finds files modified within the last 24 hours
  • Archives them into a compressed .tar.gz file
  • Moves the archive to the destination folder
• Validate argument count and paths
• Use timestamps to generate unique backup filenames
• Automate the backup using crontab

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Tools & Technologies

Category	Tools/Technologies
OS Environment	Ubuntu Linux (Skills Network Lab)
Shell Language	Bash
Utilities Used	tar, date, mv, chmod, cron
Execution Environment	Terminal / Theia IDE

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Core Components

backup.sh

The main Bash script that:

• Verifies correct usage and valid input directories
• Identifies files modified in the last 24 hours
• Creates a compressed archive (.tar.gz) with a unique timestamped name
• Moves the archive to the specified backup directory
• Can be scheduled via crontab for automation

output_log.txt

Sample script execution showing successful backup of recently modified files:

# Script Output
the first argument is important-documents
the second argument is .
ana.txt
doi.txt
zop.txt
Backup successful: /home/project/backup-1718832747.tar.gz

# Backup Directory Contents (filtered to show only backup output)
-rw-r--r-- 1 theia users 4423 Jun 19 17:32 backup-1718832747.tar.gz

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Sample Screenshots

Task	Screenshot
Script made executable	task15_executable.png
Backup archive created	task16_backup_complete.png
crontab scheduled for automation	task17_crontab.png

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Repository Structure

Linux_Shell_Backup_Project/
├── README.md                        # Project overview and usage instructions (this file)
├── backup.sh                        # Main backup script written in Bash
├── crontab_entry.txt                # cron entry to automate backup execution
├── data/                            # Input data files (used for test backup)
│   ├── ana.txt
│   ├── doi.txt
│   └── zop.txt
├── output/
│   └── output_log.txt               # Sample script execution log
├── images/
│   ├── task15_executable.png        # Screenshot: script made executable
│   ├── task16_backup_complete.png   # Screenshot: successful backup archive
│   └── task17_crontab.png           # Screenshot: crontab entry for automation

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How to Run the Script

1. Make the script executable (if not already):

   chmod +x backup.sh

2. Create an output folder (if it doesn’t exist):

   mkdir backup-folder

3. Run the backup script using the existing data/ folder as input:

   ./backup.sh data backup-folder

4. If successful, a compressed backup archive (e.g., backup-<timestamp>.tar.gz) will appear inside the backup-folder/ directory.

Note:
In the original screenshots and output log, the input folder was named important-documents as instructed in the course task.
For this repository, the input folder is named data/, but the script logic remains the same.

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Automating Backups with cron

To schedule the backup script to run automatically at a fixed time, you can set up a cron job.

For example, to run the backup daily at midnight, add the following entry to your crontab:

0 0 * * * /usr/local/bin/backup.sh /home/project/important-documents /home/project

For convenience, this cron entry is also saved in crontab_entry.txt.

To edit your crontab:

crontab -e

Note:
This path (/usr/local/bin/backup.sh) reflects the script's location in the original IBM Skills Network environment. On your local system, you may need to adjust the full path to the script and input/output folders accordingly.

Tip for Local Testing:
If you're running this project locally (not in the IBM Cloud IDE), you can use a cron job like the following:

0 0 * * * /full/path/to/Linux_Shell_Backup_Project/backup.sh /full/path/to/Linux_Shell_Backup_Project/data /full/path/to/Linux_Shell_Backup_Project/output

Be sure to replace /full/path/to/ with the absolute path to your project directory.

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License

This project was completed as part of the IBM Data Engineering Professional Certificate and is intended for educational use.

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Links

• Course Page – Hands-on Introduction to Linux Commands and Shell Scripting
• GitHub Profile
• GitHub Repository