Bash Scripting

A collection of my Bash scripts developed to practice automation, system monitoring, and CLI argument handling.

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📁 Script Directory

System Monitoring & Analysis

• analyze_memory.sh: Reports the current memory and disk usage of the machine.
• running_rss_total.sh: Analyzes the Resident Set Size (RSS) memory consumed by currently active processes.
• analyze_logs.sh: A tool to analyze logs.
  • Usage: ./analyze_logs.sh <logfile_path>

Logic & Syntax Practice

• cli_args.sh: Demonstrates how to handle and process command-line arguments.
• positional_args.sh: Showcases the use of the shift operator to navigate positional parameters.
• functions.sh: Examples of how to define and invoke reusable functions within a script.

Automation & Dev Ops

• run_postgres_container.sh: Orchestrates Docker containers. It checks for an existing Postgres container; if found, it starts it; otherwise, it pulls the image and runs a new instance.
• move_shell_files.sh: Scans a source directory for .sh files and moves them to a target directory. It includes logic to prevent overwriting existing files.
• cloudfront_download_files.sh: Network testing script that fetches files from an AWS CloudFront edge location and records the Time to First Byte (TTFB) to test cache performance.
• practice.sh: General scratchpad for testing new snippets and logic.

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🚀 How to Use

1. Clone the repo:

   git clone https://github.com/DEV270201/Bash_Scripting.git

2. Grant execution permissions:

   chmod +x *.sh

3. Run a specific script within the same directory:

   ./analyze_memory.sh

🛠 Lessons Learned

• Core Fundamentals: Mastered the use of for/while loops, arithmetic operations using $((...)), and complex if/elif/else conditional logic.
• Positional Parameters: Understood how to use $1, $@, and the shift operator to create flexible CLI tools that handle multiple arguments.
• Stream Redirection: Learned about file descriptors (1 for stdout, 2 for stderr) and how to redirect or silence outputs using > /dev/null 2>&1.
• Text Processing & Utilities: Gained hands-on experience with powerful CLI tools like awk and sed for text transformation, grep for searching, and find for file management.
• System Metrics: Used native tools like free, df, and ps to parse and display system health and resource consumption.
• Containerization: Automated environment setups by wrapping Docker lifecycle commands (pull, run, start) within Bash logic.
• Network Latency: Studied AWS Edge performance by measuring TTFB (Time to First Byte) via network requests.