I am slightly lost, I have a Debian 9 server and a Python Flask script that I am trying to launch at startup.
In the past I have used rc.local to launch things at startup but from reading it seems that it is now deprecated.
Can anyone tell me what is its replacement, what method am I best using now?
Debian 9 (like many other current Linux distributions) uses systemd to start and manage your system and services.
You'll be facing a bit of a learning curve compared to adding lines to rc.local but writing unit files (systemd jargon for what is effectively the equivalent of a start and stop script for a service) will be usefull skill to learn.
The Debian specific documentation on systemd is found on https://wiki.debian.org/systemd
The page https://wiki.debian.org/systemd/Services contains detailed step-by-step intructions for what is needed to write your own (minimal) unit file:
Create the unit file "myservice.service" in the directory /etc/systemd/system/
# /etc/systemd/system/myservice.service
[Unit]
Description=My Service
After=network.target
[Service]
Type=simple
Restart=always
ExecStart=/usr/local/bin/myservice
[Install]
WantedBy=multi-user.target
Reload systemd to pick up your changed/new unit files with: systemctl daemon-reload
Enable and start the new service
systemctl enable myservice.service
systemctl start myservice.service
You launch it using a systemd unit, like every other service.
There are numerous tutorials out on the Internet about how to set this up. Or you can just start with a skeleton unit something like:
[Unit]
Description=uWSGI instance to serve my project
After=network.target
[Service]
User=you
Group=www-data
WorkingDirectory=/home/you/project
Environment="PATH=/home/you/project/venv/bin"
ExecStart=/home/you/project/venv/bin/uwsgi --ini uwsgi.ini
[Install]
WantedBy=multi-user.target
There is no single answer, but you can use something like Supervisord:
Supervisor is a client/server system that allows its users to monitor and control a number of processes on UNIX-like operating systems.
