Action

Use screen command to prevent "Broken Pipe" messages and terminal session timeouts

Why?

When connecting to our systems (head, headnode7, lmm, etc.) via PuTTY, or terminal in mac when there is a disruption in the ssh connection, you will see a "Broken Pipe" error and loose access to any programs that were running, without being able to recover them. Screen and tmux allow you to "detatch" a session (i.e. keep it running in the background), and move on to another task in the same terminal window, or disconnect from the machine and let your code keep running.

Instructions

Basic Linux Screen Usage

After connecting to a machine from PuTTY, terminal, etc., type
```
screen
```
Run the desired program
Use the key sequence ctrl ad to detach from the screen session, this will keep it running in the background and return to your main shell
1. Note, if you do not detach the session, you can restore if the connection drops by reconnecting and running screen -r
To see a list of active screen sessions, type
```
screen -ls
```
Reattach to the screen session by typing
```
screen -r [your session id here]
```

There are many useful tutorials for using screen to preserve terminal sessions, here is one: https://linuxize.com/post/how-to-use-linux-screen/#starting-linux-screen

Basic tmux usage

After connecting to a machine from PuTTY, terminal, etc., type
```
tmux
```
Run the desired program
Use the key sequence Ctrl+b d to detatch the session
To see a list of active tmux sessions
```
tmux -ls
```

To reattach a tmux session type

tmux attach-session -t [your session id here]

There are many useful tutorials for using tmux to preserve terminal sessions, here is one: https://linuxize.com/post/getting-started-with-tmux/#starting-your-first-tmux-session

Need more help? Contact the ITS Service Desk.

How-to: Using screen or tmux to preserve a Linux terminal session

Action

Instructions

Basic Linux Screen Usage

Basic tmux usage