Frequently Asked Question

How can I keep a process running after I log out, nohup vs disown vs &?

A plain command & runs the program in the background but does not detach it from the shell: when you exit, bash sends SIGHUP to all its jobs and they die. The three idiomatic ways to survive that hangup are nohup, disown, and a terminal multiplexer. nohup command & arranges before launch that the process ignores SIGHUP and redirects its standard output and error to nohup.out so they have somewhere to go after the terminal is gone.

disown is the same idea applied after the fact: start the job normally, then run disown %1 (or disown -h %1 to leave it in the jobs table but mark it hangup-immune). For anything non-trivial, especially over SSH, the right answer is tmux or screen, which run the process inside a persistent virtual terminal you can detach from and reconnect to from any machine. Picking nohup or disown is fine for fire-and-forget batch jobs; pick tmux for anything you want to come back and interact with.