tmux for persistent sessions in Linux CLI - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is tmux used for in Linux?

tmux is a terminal multiplexer that lets you create, manage, and switch between multiple terminal sessions inside one window. It keeps sessions running even if you disconnect.

beginner

How do you start a new tmux session named work?

Use the command tmux new -s work. This creates a new session called 'work' where you can run commands.

beginner

How can you detach from a tmux session without closing it?

Press Ctrl + b then d. This detaches you from the session but keeps it running in the background.

beginner

How do you list all active tmux sessions?

Run tmux ls or tmux list-sessions. It shows all sessions you can attach to.

beginner

How do you re-attach to a tmux session named work?

Use tmux attach -t work. This opens the session named 'work' so you can continue where you left off.

What does tmux allow you to do?

A Keep terminal sessions running after disconnecting

B Automatically update Linux packages

C Create graphical windows

D Monitor CPU temperature

tmux lets you keep terminal sessions alive even if you disconnect, so you can resume work later.

Which key combination detaches you from a tmux session?

A Ctrl + z

B Ctrl + b then d

C Ctrl + c

D Ctrl + x

Pressing Ctrl + b then d detaches you from the tmux session without closing it.

How do you start a new tmux session named 'dev'?

A tmux open dev

B tmux start dev

C tmux new -s dev

D tmux create dev

The command 'tmux new -s dev' creates a new session named 'dev'.

What command lists all tmux sessions?

A tmux ls

B tmux show

C tmux sessions

D tmux list

'tmux ls' or 'tmux list-sessions' shows all active tmux sessions.

How do you re-attach to a session named 'work'?

A tmux start work

B tmux connect work

C tmux resume work

D tmux attach -t work

Use 'tmux attach -t work' to re-attach to the session named 'work'.

Explain how tmux helps keep your work safe when you lose connection to a server.

Think about what happens if your internet drops while working remotely.

Describe the steps to create, detach, and then re-attach to a tmux session.

Focus on commands and key presses in order.

Practice

1. What is the main benefit of using tmux for command line sessions?

easy

A. It provides a graphical interface for Linux commands.

B. It automatically updates your system packages.

C. It allows you to keep sessions running and return to them later.

D. It replaces the need for a terminal emulator.

Solution

1. Step 1: Understand tmux purpose

   tmux is a terminal multiplexer that lets you create, detach, and reattach sessions.

2. Step 2: Identify main benefit

   This means you can keep your command line work running and come back anytime without losing progress.

3. Final Answer:

   It allows you to keep sessions running and return to them later. -> Option C

4. Quick Check:

   tmux keeps sessions persistent = A [OK]

Hint: tmux saves your work session to return anytime [OK]

Common Mistakes:

• Thinking tmux updates software
• Confusing tmux with GUI tools
• Believing tmux replaces terminal emulator

2. Which of the following commands correctly creates a new named tmux session called work?

easy

A. tmux open -n work

B. tmux start work

C. tmux create session work

D. tmux new -s work

Solution

1. Step 1: Recall tmux session creation syntax

   The correct syntax to create a named session is tmux new -s session_name.

2. Step 2: Match command to syntax

   tmux new -s work matches this syntax exactly, creating a session named 'work'.

3. Final Answer:

   tmux new -s work -> Option D

4. Quick Check:

   tmux new -s name creates session = A [OK]

Hint: Use 'tmux new -s name' to start named session [OK]

Common Mistakes:

• Using 'start' instead of 'new'
• Omitting the '-s' flag for naming
• Using incorrect verbs like 'create' or 'open'

3. What will be the output of the command tmux ls if you have two sessions named dev and test running?

medium

A. No sessions found

B. dev: 1 windows (created Thu Jun 1 10:00:00 2023)\ntest: 1 windows (created Thu Jun 1 10:05:00 2023)

C. Session dev attached\nSession test attached

D. Error: tmux command not found

Solution

1. Step 1: Understand tmux ls output

   This command lists all active tmux sessions with their names and window counts.

2. Step 2: Match output to sessions

   With two sessions 'dev' and 'test', it shows each with window count and creation time.

3. Final Answer:

   dev: 1 windows (created Thu Jun 1 10:00:00 2023) test: 1 windows (created Thu Jun 1 10:05:00 2023) -> Option B

4. Quick Check:

   tmux ls lists sessions = C [OK]

Hint: tmux ls lists all active sessions by name [OK]

Common Mistakes:

• Expecting 'No sessions' when sessions exist
• Confusing attached status with listing
• Thinking tmux ls shows errors if tmux installed

4. You tried to reattach to a tmux session with tmux attach -t mysession but got the error: no sessions. What is the most likely cause?

medium

A. The session named 'mysession' does not exist.

B. You forgot to install tmux.

C. You need to use tmux new instead of attach.

D. The terminal emulator is not supported.

Solution

1. Step 1: Analyze error message meaning

   The error 'no sessions' means tmux cannot find a session with the given name.

2. Step 2: Identify cause of error

   This usually happens if the session was never created or was closed.

3. Final Answer:

   The session named 'mysession' does not exist. -> Option A

4. Quick Check:

   Attach error 'no sessions' means session missing = B [OK]

Hint: Check session exists before attaching [OK]

Common Mistakes:

• Assuming tmux is not installed
• Using attach instead of new incorrectly
• Blaming terminal emulator

5. You want to create a tmux session named project, detach from it, and later reattach. Which sequence of commands achieves this correctly?

hard

A. tmux new -s project; Ctrl+b d; tmux attach -t project

B. tmux start project; Ctrl+c; tmux attach project

C. tmux create -n project; Ctrl+b x; tmux reattach project

D. tmux open project; Ctrl+d; tmux attach-session project

Solution

1. Step 1: Create and detach session

   Use tmux new -s project to create session, then press Ctrl+b d to detach safely.

2. Step 2: Reattach session

   Use tmux attach -t project to reattach to the named session later.

3. Final Answer:

   tmux new -s project; Ctrl+b d; tmux attach -t project -> Option A

4. Quick Check:

   Create, detach, attach with correct commands = D [OK]

Hint: Use Ctrl+b d to detach, attach with tmux attach -t name [OK]

Common Mistakes:

• Using wrong tmux commands like start or create
• Pressing wrong keys to detach
• Omitting '-t' when attaching