Tiny-RSS update in background using SystemD

Before you can start using tt-rss properly, you have to tell him to update your feeds!  Here is the complete how to do it with SystemD

Systemd is an init system used in Linux distributions to bootstrap the user space. Subsequently to booting, it is used to manage system processes. It is a replacement for the UNIX System V and Berkeley Software Distribution (BSD) init systems. The goal is unification of basic Linux configurations and service behaviors across all distributions

Create a new file /lib/systemd/system/ttrss_backend.service

with content

[Unit]
Description=ttrss_backend
After=network.target mysql.service postgresql.service

[Service]
User=www-data
ExecStart=/home/waltercedric.com/subdomains/rss/update_daemon2.php

[Install]
WantedBy=multi-user.target

 And then run 

systemctl enable ttrss_backend.service
service ttrss_backend start

You can use journalctl -u ttrss_backend to look through daemon console output.