Run a process on a Linux server with Systemd
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For iSignif, I use Sidekiq for background jobs like emails. I run it as a simple command like
bundle exec sidekiqI want that this command at server start, and retry it if it fails. I found that an easy way is to use Systemd.
So I just had to create a new service. It’s a simple file /etc/systemd/system/isignif_production_sidekiq.service
# /etc/systemd/system/isignif_production_sidekiq.service
[Unit]
Description=isignif_production_sidekiq
After=syslog.target
[Install]
WantedBy=multi-user.target
[Service]
Type=simple
# the directory where I want to execute the command and the command
WorkingDirectory=/var/www/isignif/current
ExecStart=/home/isignif/.rvm/rubies/ruby-3.2.7/bin/bundle exec sidekiq
User=isignif
Group=isignif
UMask=0002
# failing strategy
RestartSec=1
Restart=on-failure
Environment=RAILS_ENV=production
# put content of `echo $PATH` to add RVM
Environment=PATH=/home/isignif/.rvm/gems/ruby-3.2.7/bin:/home/isignif/.rvm/gems/ruby-3.2.7@global/bin:/home/isignif/.rvm/rubies/ruby-3.2.7/bin:/home/isignif/.rvm/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin
The main challenge I got was to make Systemd uses the Ruby version from RVM. The quick and dirty solution I found was to copy/paste the user’s $PATH variable inside the Environment section like this
Environment=PATH=/home/isignif/.rvm/gems/ruby-3.2.7/bin:/home/isignif/.rvm/gems/ruby-3.2.7@global/bin:/home/isignif/.rvm/rubies/ruby-3.2.7/bin:/home/isignif/.rvm/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/binOnce done, the service can be started as a single command like:
sudo systemctl start isignif_production_sidekiq.serviceAnd you can get the logs using:
journalctl -u isignif_production_sidekiq.serviceSee other related posts
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