Custom Systemd Scripts & Package Updates Question

[Zoot]

So... I have a media server at home which currently runs Windows. I'm interested in putting Debian Buster on it instead, since it's more light weight than Windows and could be left for months & months without reboots. I haven't used Debian since Jessie, but I used Squeeze & Wheezy for a number of years, but that was on the desktop instead of the server.

I've been toying with Buster in a VM lately to test stuff out before I take the plunge. I've more or less got to terms with creating services, groups, user accounts and all the permissions to get the various applications to play nice with each other. (Plex/Transmission/Deluge/Sonarr/Radarr/Jackett etc.)

One thing that's got me concerned is that in order to get the applications to be able to access the files they create, I've had to create custom systemd scripts to run all the services as the same group & user account.

Brings me to my question - Certain applications handle the service creation for you when you install the package, others don't (which I would prefer). For the ones that create the services automatically (Transmission & Plex are examples), if I use a custom systemd script, how is this handled if their packages are updated? Do they screw up the custom systemd scripts I've created and revert the users the services run as to their defaults?

[Zoot]

Okay... the systemd page on the Debian Wiki has answered my question. Guess I should RTFM the next time.

I'm a bit of a n00b on the server side of things.

https://wiki.debian.org/systemd#Creatin ... g_services