Your booking system or bot runs on a Linux server, someone restarts it, the console says it started fine and it actually isn't running. This is the official reference for '.service' files, which tell systemd how to start, supervise and stop each program on the server. It is not software you install: it is the manual that explains what each option means.
Who this is NOT for
If your business runs on Google Workspace, Shopify or any cloud service you don't administer yourself, this is useless to you: you have no '.service' files to configure. It isn't a tutorial either. It is a reference manual in technical English that assumes you already know what fork(), execve() and a socket are. If nobody on your team uses the terminal, don't read it yourself. Hand it to whoever manages your server.
One detail in this manual is worth the whole entry. If a service doesn't declare Type=, systemd defaults to 'simple', and the manual itself says that in this mode 'systemctl start' reports success even when the program can't run, for example when the binary is missing or the user doesn't exist. The same text says Type=exec is usually the better choice, because it does report the failure. Plenty of people trust that 'started' and find out about the problem when a customer complains. The copy we pulled is Arch Linux's and doesn't say which systemd version it documents, so your server may run another version with different options. Also, the text we could pull cuts off at the Type= section, so this entry doesn't cover the remaining options.
Your first step
Open the page and read only the Type= section. Then check the [Service] section of the '.service' file for your most important program. If it has ExecStart= but no Type=, it runs in 'simple' mode and a failed start can look like a success.
The systemd.service(5) — Arch manual pages implementation guide
The project belongs to man.archlinux.org and it is free: the link beside asks for nothing. The guide to set it up without getting lost is ours: step by step, common mistakes and a checklist. Leave your email and we will send it.
No spam. Unsubscribe anytime.