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Port Management

View and manage processes using network ports.

Port Management Port Management showing active network connections and listening ports

Overview

Port Management helps developers and power users see what's running on their Mac's network ports and terminate processes when needed.

Understanding Ports

What is a Port?

A port is a communication endpoint. When applications need network access, they "listen" on specific ports:

  • Port 80 - HTTP web traffic
  • Port 443 - HTTPS secure web traffic
  • Port 22 - SSH connections
  • Port 3000 - Common development server port
  • Port 8080 - Alternative HTTP port
  • Port 5432 - PostgreSQL database
  • Port 3306 - MySQL database
  • Port 27017 - MongoDB database

Connection States

State Meaning
LISTEN Waiting for incoming connections
ESTABLISHED Active connection
TIME_WAIT Connection closing, waiting to ensure delivery
CLOSE_WAIT Remote side closed, waiting for local close
CLOSED Connection terminated

Interface

Connection Table

Column Description
Port Local port number
Process Application name
PID Process ID
Protocol TCP or UDP
State Connection state
Remote Remote address (if connected)
Actions Kill button

Toolbar

  • Search - Filter by port number or process name
  • State Filter - Show only specific states
  • Refresh - Update connection list
  • Auto-refresh - Toggle automatic updates

Common Tasks

Find What's Using a Port

  1. Open Port Management
  2. Enter port number in search (e.g., "3000")
  3. See the process using that port

Kill a Process by Port

  1. Find the connection in the list
  2. Click Kill button
  3. Confirm the action
  4. Process terminated

View All Listening Ports

  1. Set State filter to "LISTEN"
  2. See all services waiting for connections
  3. Useful for security audits

Kill Options

Graceful Termination (SIGTERM)

  • Default option
  • Allows process to clean up
  • May fail for stuck processes

Force Kill (SIGKILL)

  • Immediate termination
  • No cleanup opportunity
  • Use when graceful fails
  • May cause data loss

Common Port Conflicts

Development Servers

Problem: "Port 3000 already in use"

Solution:

  1. Find process using port 3000
  2. Kill it or use different port
  3. Restart your development server

Database Connections

Problem: Can't connect to database

Check:

  1. Is database server running?
  2. Is it listening on expected port?
  3. Any firewall blocking?

Zombie Processes

Problem: Port shows in use but app closed

Solution:

  1. Find the orphaned process
  2. Force kill it
  3. Port now available

Safety Warnings

System Processes

Some processes are critical:

  • launchd - System process manager
  • kernel_task - Core system process
  • WindowServer - Display server

Never kill these - may require restart.

Protected Ports

Ports below 1024 are "privileged":

  • Require root access to bind
  • Usually system services
  • Kill with caution

Command Line Equivalent

MyMacCleaner uses these commands internally:

# List all connections
lsof -i -P -n

# Find specific port
lsof -i :3000

# Kill process by PID
kill -15 <PID>      # Graceful
kill -9 <PID>       # Force

# Kill process on port (one-liner)
kill -9 $(lsof -t -i:3000)

Tips

  1. Development workflow - Keep Port Management open while coding
  2. Port conflicts - Check before starting new services
  3. Security - Review unknown listening processes
  4. Debugging - Verify services are running on expected ports

Keyboard Shortcuts

Shortcut Action
Cmd + R Refresh list
Cmd + F Focus search
Cmd + K Kill selected process
Cmd + C Copy process info