Day 5: Master Advanced Linux Shell Scripting for DevOps User Management

Tasks:

1. Create Directories Using a Shell Script.

2. Create a Script to Backup All Your Work.

3. Read About Cron and Crontab to Automate the Backup Script.

4. Read About User Management.

Solutions:

1. Here's a bash script for the first task, creating directories with a dynamic name:

    #!/bin/bash 
   
    if [ "$#" -ne 3 ]; then 
        echo "Usage: $0 <directory_name> <start_number> <end_number>" 
        exit 1 
    fi
   
    directory_name="$1" 
    start_number="$2" 
    end_number="$3" 
   
    if [ "$start_number" -gt "$end_number" ]; then echo "Start number should be less than or equal to end number." exit 1 
    fi 
   
    for 
      ((i=start_number; i<=end_number; i++)); do         dir_name="${directory_name}${i}" 
    mkdir "$dir_name" 
    echo "Created directory: $dir_name" 
    done
   

   Save this script in a file, e.g., createDirectories.sh, and make it executable using chmod +x createDirectories.sh.

   To run the script, use the following commands:

    ./createDirectories.sh day 1 90
   

   This will create directories named day1, day2, day3, and so on up to day90.

2. Backup Your Work:

   For the second task, creating a backup script, you can create a script like this:

    #!/bin/bash 
   
    # Set the source directory to backup source_directory="/path/to/your/source"
   
    # Set the backup directory 
    backup_directory="/path/to/your/backup"
   
    # Create a timestamp to include in the backup folder name 
    timestamp=$(date +%Y%m%d%H%M%S)
   
    # Create a backup file with a timestamp 
    final_file="$backup_directory/file_backup-$timestamp.tgz"
   
    # Create the backup
    if tar czf "$final_file" -C "$source_directory" .; then
      echo "Backup Complete"
    else
      echo "Backup Failed"
    fi
   

   Save this script in a file, e.g., backup.sh, and make it executable using chmod +x backup.sh.

   To automate this backup script using Cron, you can add an entry to your user's crontab by running crontab -e and adding a line like this to run the script daily at a specific time:

    0 2 * * * /path/to/backup.sh
   

   This will run the backup.sh script every day at 2:00 AM. Adjust the timing as needed.

3. User Management in Linux:

   For the third task, you can create two users and display their usernames using the following commands:

    # Create the first user 
    sudo useradd user1 
   
    # Set a password for the first user 
    sudo passwd user1 
   
    # Create the second user 
    sudo useradd user2 
   
    # Set a password for the second user 
    sudo passwd user2 
   
    # Display the usernames 
    echo "User 1: user1" echo "User 2: user2"
   

   This will create two users, user1 and user2, and display their usernames as specified.

   "I believe this article will be beneficial, allowing you to uncover fresh insights and gain enriching knowledge."

   Happy Learning🙂

   Parth Sharma