Below are the default paths for the application data directory

All instances of $USER are placeholders for the user the application is running under.

C:\ProgramData\Sonarr

Unless otherwise specified Sonarr will store it's application data in the home folder of the user Sonarr is running under /home/$USER/.config/Sonarr or ~/.config/Sonarr

For apt repo based installs, it defaults to /var/lib/Sonarr

/Users/$USER/.config/Sonarr or ~/.config/Sonarr

If you are using the SynoCommunity package for Sonarr, this is where you should expect to find your appdata. If you are using Docker on your Synology NAS, look below in the Docker section.

/volume1/@appdata/nzbdrone/.config/Sonarr

/volume1/@appstore/nzbdrone/.config/Sonarr

The SynoCommunity still uses the original package name nzbdrone for the underlying package name

/share/MD0_DATA/homes/admin/.config/Sonarr

/share/CACHEDEV1_DATA/Sonarr_CONFIG

/config

The -data= argument forces the location of the AppData folder, so your startup command may be forcing a specific location. This is required when trying to run multiple instances. On Windows this would be /data=

The -nobrowser argument refrains from launching/opening the browser on startup. On Windows this would be /nobrowser