Does the fact that I have lost the command prompt mean that the process is still running?
Unlikely. The process will have a connection to the virtual terminal of ssh, which will eventually time out and kill all the processes associated with that terminal - though gunicorn could be written in a manner that it doesn't exit when the controlling terminal disappears.
How do I get back to the command prompt without killing the process?
If the terminal is still alive, hit CTRL+Z to get back to the command prompt, then write
bg to place gnuicorn in the background (and use
fg to get back to the process so you can kill it - e.g. with
Starting it as either
gunicorn -w 4 myapp:app & will place the process in the background of the shell immediately - though depending on the server it might still get killed when your ssh session ends. Running
nohup gunicorn -w 4 myapp:app & will ensure the process to run even when you disconnect. Read the man page of
Another option is to run the process in a terminal that allows you to reattach to it. That's what the GNU screen or the tmux allows you to do - effectivly allowing you to disconnect the ssh session, connect back later on and reattach to an existing terminal session.
How do I come back and monitor the process later?
You can't, unless you run the process inside a GNU screen or tmux session - in which case the docs/tutorials for screen or tmux will tell you the detail - or you've started the server to run as a service/in the background.
How do I eventually kill the process?
Most server programs will have a managment interface (e.g. commands you'll have to run), and you'll have to find the relevant information in the documentation.
Or they integrate themselves in the linux/unix startup and service management procedures, in which case you manage them as any other services , e.g.
/sbin/service fooserver start
/sbin/service fooserver stop on some linux distros.
Or you have to do it manually. Find the process by running
ps -ef |grep fooserver to find its pid, and kill it,
kill <the pid>. Or look in the documentation if the erver can write a "pid file" when it starts up, so you can find the process id in that file later on.
Now, it seems at least gunicorn has a -D argument, which is used to place the server in the background, disconnecting it from the terminal, so it doesn't get killed when your ssh/putty connection disconnects. See http://gunicorn.org/configure.html#server-mechanics
You'll then have to manage/monitor it manually, i.e. kill it as I mentioned above, monitor it through the log file it produces - or any integrated monitoring webapp or commands gnuicorn might have.
The intent here is clearly for someone to package gnuicorn for a particular linux/*nix variant, and write the relevant scripts and config files to integrate it into the native service management of the distro. (e.g. a standard script under /etc/init.d/ to start and stop the server, used on many