Tmux — the lifehack that keeps your SSH session alive through internet dropouts

Tmux — the lifehack that keeps your SSH session alive through internet dropouts

Working on a server over SSH and worried that an internet dropout or an accidentally closed terminal window will kill a long-running task? There's a simple and elegant fix — tmux. It's a terminal multiplexer that runs commands in a background "session" on the server, living independently of your SSH connection.

The problem

When your SSH connection drops — internet flickers, you close the window, your laptop restarts — every process started in that terminal dies. If a long task was running (an update, a backup, a long render), it's simply lost.

What tmux does

Tmux keeps your commands in a session that lives on the server independent of SSH. Connection drops → the session keeps running. You reconnect → everything is still there, as if nothing happened.

How to use it

1. Install on the server (ubuntu/debian):

sudo apt install -y tmux

2. Start a named session:

tmux new -s hermes

The -s hermes flag names the session — you reconnect to it by name. Now you're inside tmux and can run whatever you need.

3. "Detach" without closing the session:

Inside tmux press Ctrl + B, then D (detach). The session keeps running in the background, and you return to a normal terminal. Now you can safely close SSH or lose internet — your commands keep going.

4. Reconnect to the session:

tmux attach -t hermes

Everything is right where you left it — no losses.

Quick cheat sheet

Things to keep in mind

• A tmux session lives as long as the server does. Rebooting the server kills sessions — that's normal.
• Don't just close the window — detach first (Ctrl+B, D), otherwise tmux may terminate the session.
• Sessions accumulate — check tmux ls periodically and kill unneeded ones (kill-session); they eat server memory.
• Don't keep sudo passwords and secrets in a tmux session — everything there is plain text.

Quick practice

tmux new -s test
# inside run: top
Ctrl + B, D        # detach
# close the SSH window, reopen
tmux attach -t test   # confirm top is still running

Why it matters to me

If you run hermes (or any long task) inside a tmux session on the server, it won't be interrupted by an internet dropout. That's exactly what you need when working with a remote server and constant reconnections.