While checking the status of packages using dpkg, it is possible to see a ‘rc’ state for some unused packages, this corresponds to:
r: the package was marked for removal
c: the configuration files are currently present in the system
In other words: the package is not completely removed (config files are still present), but not installed anymore (and obviously not used).
As the developer says, OpenMediaVault is:
“The next generation network attached storage (NAS) solution based on Debian Linux.
It contains services like SSH, (S)FTP, SMB/CIFS, DAAP media server, RSync, BitTorrent client and many more.”
“Thanks to the modular design of the framework it can be enhanced via plugins. OpenMediaVault is primarily designed to be used in home environments or small home offices, but is not limited to those scenarios. It is a simple and easy to use out-of-the-box solution that will allow everyone to install and administrate a Network Attached Storage without deeper knowledge.”