tmux Command Linux: Complete Terminal Multiplexer Guide with Examples

The tmux command is a powerful terminal multiplexer that allows you to create multiple terminal sessions, split windows, and manage complex terminal workflows efficiently. Whether you’re a system administrator, developer, or Linux enthusiast, mastering tmux can significantly boost your productivity by enabling you to run multiple processes simultaneously within a single terminal window.

What is tmux?

Tmux (Terminal Multiplexer) is a command-line application that lets you create, manage, and switch between multiple terminal sessions. Think of it as a window manager for your terminal, allowing you to:

• Create multiple sessions that persist even after disconnecting
• Split terminal windows into multiple panes
• Share sessions between different users
• Run long-running processes without losing them when disconnecting
• Organize your workspace with multiple windows and panes

Installing tmux

Before diving into tmux commands, you need to install it on your system:

Ubuntu/Debian:

sudo apt update
sudo apt install tmux

CentOS/RHEL/Fedora:

sudo yum install tmux
# or for newer versions
sudo dnf install tmux

macOS (using Homebrew):

brew install tmux

Verify the installation:

tmux --version

Basic tmux Commands

Starting and Managing Sessions

Let’s start with the fundamental tmux commands for session management:

1. Creating a New Session

# Create a new tmux session
tmux

# Create a named session
tmux new -s mysession

# Create a session with a specific name and command
tmux new -s development -c ~/projects

Expected Output: You’ll see a new terminal with a green status bar at the bottom showing session information.

2. Listing Active Sessions

tmux list-sessions
# or shorthand
tmux ls

Sample Output:

development: 1 windows (created Mon Aug 25 01:36:15 2025)
mysession: 2 windows (created Mon Aug 25 01:30:22 2025)

3. Attaching to Sessions

# Attach to the most recent session
tmux attach

# Attach to a specific session
tmux attach -t mysession

# Attach to session by number
tmux attach -t 0

4. Detaching from Sessions

While inside a tmux session, use the key combination:

Ctrl+b, then d

This detaches you from the session without terminating it.

Key Bindings and Shortcuts

Tmux uses a prefix key (default: Ctrl+b) followed by other keys to execute commands. Here are the essential key bindings:

Session Management

• Ctrl+b, d – Detach from current session
• Ctrl+b, s – List and switch sessions
• Ctrl+b, $ – Rename current session

Window Management

• Ctrl+b, c – Create new window
• Ctrl+b, n – Next window
• Ctrl+b, p – Previous window
• Ctrl+b, 0-9 – Switch to window by number
• Ctrl+b, , – Rename current window
• Ctrl+b, & – Kill current window

Pane Management

• Ctrl+b, % – Split pane vertically
• Ctrl+b, " – Split pane horizontally
• Ctrl+b, arrow keys – Navigate between panes
• Ctrl+b, x – Kill current pane
• Ctrl+b, z – Zoom/unzoom current pane

Advanced Window and Pane Operations

Working with Panes

Panes are subdivisions within a tmux window. Here’s how to work with them effectively:

Creating Panes

# Split current window vertically (side by side)
Ctrl+b, %

# Split current window horizontally (top and bottom)
Ctrl+b, "

You can also create panes with specific commands:

tmux split-window -h    # horizontal split
tmux split-window -v    # vertical split

Resizing Panes

# Resize pane (hold Ctrl+b and use arrow keys)
Ctrl+b, Ctrl+arrow keys

# Resize by specific amount
tmux resize-pane -L 10  # Left by 10 columns
tmux resize-pane -R 5   # Right by 5 columns
tmux resize-pane -U 3   # Up by 3 rows
tmux resize-pane -D 2   # Down by 2 rows

Practical Example: Development Environment Setup

Let’s create a typical development environment with tmux:

# 1. Start a new named session
tmux new -s devwork

# 2. Create a horizontal split (Ctrl+b, ")
# Top pane: for editing
# Bottom pane: for running commands

# 3. In the bottom pane, create a vertical split (Ctrl+b, %)
# Bottom-left: for git commands
# Bottom-right: for system monitoring

# 4. Navigate between panes using Ctrl+b + arrow keys

Result: You’ll have a three-pane layout perfect for development work.

tmux Configuration

Customize tmux behavior by creating a configuration file at ~/.tmux.conf:

Basic Configuration Example

# Change prefix key from Ctrl+b to Ctrl+a
set -g prefix C-a
unbind C-b
bind C-a send-prefix

# Enable mouse mode
set -g mouse on

# Start windows and panes at index 1
set -g base-index 1
setw -g pane-base-index 1

# Reload config file
bind r source-file ~/.tmux.conf \; display-message "Config reloaded!"

# Split panes using | and -
bind | split-window -h
bind - split-window -v

# Enable vi mode
setw -g mode-keys vi

Apply the configuration:

tmux source-file ~/.tmux.conf

Session Sharing and Remote Work

Tmux excels in remote work scenarios where you need persistent sessions:

Creating Shared Sessions

# Create a session that multiple users can attach to
tmux new -s shared-session

# Another user can attach to the same session
tmux attach -t shared-session

SSH and tmux Integration

Perfect for maintaining work sessions across SSH connections:

# SSH to remote server
ssh user@server

# Start or attach to tmux session
tmux attach -t work || tmux new -s work

# Even if SSH disconnects, your session continues running

Practical Use Cases

1. System Monitoring Dashboard

# Create monitoring session
tmux new -s monitoring

# Split into four panes for different monitoring tools
# Top-left: htop
# Top-right: iostat
# Bottom-left: tail logs
# Bottom-right: network stats

2. Development Workflow

# Create development session
tmux new -s coding -c ~/project

# Window 0: Editor (vim/nano)
# Window 1: Testing (Ctrl+b, c)
tmux new-window -n testing

# Window 2: Server (Ctrl+b, c)
tmux new-window -n server

3. Long-running Tasks

# Start a session for long-running processes
tmux new -s background-tasks

# Run backup script, compilation, or data processing
# Detach safely knowing processes continue

Troubleshooting Common Issues

Session Won’t Start

If tmux won’t start, check if there are dead sessions:

tmux kill-server  # Kills all tmux sessions
tmux new -s fresh-start

Panes Not Responding

Sometimes panes become unresponsive:

# Kill specific pane
Ctrl+b, x

# Kill entire window
Ctrl+b, &

Configuration Not Loading

# Manually reload configuration
tmux source-file ~/.tmux.conf

# Check configuration syntax
tmux show-options -g

Advanced tmux Features

Copy Mode

Navigate and copy text within tmux:

# Enter copy mode
Ctrl+b, [

# Navigate with arrow keys or vi commands
# Space to start selection
# Enter to copy selection
# Ctrl+b, ] to paste

Session Templates with tmuxinator

For complex setups, consider using tmuxinator:

# Install tmuxinator
gem install tmuxinator

# Create project template
tmuxinator new myproject

Best Practices

1. Use meaningful session names: Instead of default numbers, use descriptive names like “work”, “monitoring”, or “development”.
2. Customize your prefix key: Many users prefer Ctrl+a over Ctrl+b for easier access.
3. Enable mouse mode: Makes pane resizing and selection more intuitive.
4. Create reusable configurations: Build templates for common workflows.
5. Regular cleanup: Periodically kill unused sessions to keep things organized.

Conclusion

The tmux command is an indispensable tool for Linux users who work extensively with terminals. It transforms a single terminal into a powerful workspace management system, enabling you to organize multiple tasks, maintain persistent sessions, and work more efficiently.

From basic session management to advanced pane layouts and custom configurations, tmux offers the flexibility to adapt to any workflow. Whether you’re managing servers, developing applications, or monitoring systems, integrating tmux into your daily routine will significantly enhance your productivity and make terminal-based work more enjoyable.

Start with the basic commands covered in this guide, gradually incorporating more advanced features as you become comfortable. With practice, tmux will become second nature, and you’ll wonder how you ever managed without this powerful terminal multiplexer.