Ubuntu: Nohup Run Python as Background Process and Capture Log to File

Run python program

main.py run --username desmond

Run python in background

nohup python main.py run --username desmond &

More:

• nohup [COMMAND] &: run as background
• python -u: disable output buffering (to ensure exception are shown immediately)
• [COMMAND] > /logs/main.log 2>&1: capture std and err output into log
• $! > run.pid: save process id into file (pid can be use to check if process is still alive, and kill it if necessary)

nohup python -u main.py run --username desmond > /logs/main.log 2>&1 & echo $! > desmond.pid

Check log

tail -f /logs/main.log

Check pid is running

ps -p "$(cat desmond.pid)"