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Last tested: Oct 15, 2020
example flag --no-daemonize
TLDR: daemonize runs programs in the background.
If you add the --no-daemonize flag, Looker will stop when the user kills the terminal session on the instance.
daemonize runs a command as a Unix daemon. As defined in W. Richard Stevens’ 1990 book, UNIX Network Programming (Addison-Wesley, 1990), a daemon is “a process that executes ‘in the background’ (i.e., without an associated terminal or login shell) either waiting for some event to occur, or waiting to perform some specified task on a periodic basis.”