When a shell exits (maybe while logging out of a SSH session), the HUP ('hang up') signal is send to all of its child processes, causing them to terminate. If you require a long-running process to continue after exiting shell, you'll need the nohup
command. Prefixing any command with nohup
causes the command to become immune to HUP signals. Additionally, STDIN is being ignored and all output gets redirected to local file ./nohup.out
.
- Applying nohup to a long-running debian upgrade:
nohup apt-get -y upgrade
nohup COMMAND [ARG]...
nohup OPTION