09. COMMAND / ADMIN TOOLS

As a Computer Systems Analyst, proficiency in command prompt and Linux commands can significantly enhance your efficiency and troubleshooting capabilities. Here are some essential and advanced commands that can help you:

Windows Command Prompt Commands

1. System Information and Management
   
   • systeminfo: Displays detailed configuration information about a computer and its operating system.
   • ipconfig: Displays all current TCP/IP network configuration values.
   • tasklist: Lists all running processes.
   • taskkill: Terminates tasks by process ID (PID) or image name.
   • sfc /scannow: Scans and repairs system files.
2. File and Directory Management
   
   • dir: Lists files and directories.
   • cd: Changes the current directory.
   • mkdir: Creates a new directory.
   • del: Deletes one or more files.
   • copy: Copies files from one location to another.
   • move: Moves files from one location to another.
   • robocopy: Robust file copy utility with many options for copying files and directories (advanced replacement for xcopy).
3. Network Troubleshooting
   
   • ping: Checks connectivity to a specific IP address or hostname.
   • tracert: Traces the route taken by packets to reach a destination.
   • netstat: Displays network statistics and connections.
   • nslookup: Queries DNS servers.
   • arp: Displays and modifies the IP-to-Physical address translation tables.
4. System Monitoring
   
   • taskmgr: Opens Task Manager.
   • eventvwr: Opens Event Viewer to check system logs.
   • perfmon: Opens Performance Monitor.

Linux Commands

1. System Information and Management
   
   • uname -a: Displays all system information.
   • df -h: Shows disk space usage in a human-readable format.
   • free -h: Displays memory usage in a human-readable format.
   • top or htop: Displays real-time system performance statistics.
   • ps aux: Lists all running processes.
   • kill [PID]: Terminates a process by its PID.
2. File and Directory Management
   
   • ls -lah: Lists files and directories with detailed information.
   • cd: Changes the current directory.
   • mkdir: Creates a new directory.
   • rm -rf: Recursively removes directories and their contents (use with caution).
   • cp -r: Copies files and directories recursively.
   • mv: Moves or renames files and directories.
   • find: Searches for files and directories.
   • tar -czvf archive.tar.gz /path/to/directory: Archives and compresses files.
3. Network Troubleshooting
   
   • ping: Checks connectivity to a specific IP address or hostname.
   • traceroute: Traces the route taken by packets to reach a destination.
   • netstat -tuln: Displays listening ports and their associated programs.
   • ifconfig or ip addr: Displays network interface configuration.
   • nslookup: Queries DNS servers.
   • ssh user@hostname: Connects to a remote machine via SSH.
4. System Monitoring and Logging
   
   • dmesg: Prints kernel and boot messages.
   • tail -f /var/log/syslog: Monitors system log in real-time.
   • journalctl: Queries and displays logs from systemd journal.
5. User and Permissions Management
   
   • sudo: Executes a command with superuser privileges.
   • chmod: Changes file permissions.
   • chown: Changes file owner and group.
   • usermod -aG group user: Adds a user to a group.

Advanced Tools and Scripts

1. Automation and Scripting
   
   • Batch Scripting (Windows): Create .bat or .cmd files to automate repetitive tasks.
   • Shell Scripting (Linux): Use bash scripts (.sh) to automate tasks.
   • PowerShell (Windows): Advanced scripting and automation tool.
2. Version Control
   
   • git: Version control system for tracking changes in files and coordinating work on those files among multiple people.
3. Text Processing and Data Manipulation
   
   • grep: Searches text using patterns.
   • awk: Pattern scanning and processing language.
   • sed: Stream editor for filtering and transforming text.