Music Servers/External Drives

Lanx0003 makes a good point.  If you use an external hard drive, BACK IT UP REGULARLY!!!  They have a tendency to fail with little or no notice.  I keep a clone of my main drive connected to a difference stereo in the house.  I find that the Seagates are the most reliable, but don't risk a catastrophic loss of a curated collection for failing to spend an additional $150 or so on a second hard drive.

 In addition, SSD reads data without generating vibration and is supposed to give less electric noise that compromises SQ.

Yes, although  as I understand it, this isn't  an issue if you're only using an HDD for local library storage with Roon (and not as the location where Roon Core is installed).  In Roon's storage settings, you set a path to the device.  Then Roon continually monitors it for new files.  When it finds them, it integrates them into your Roon library. In that scenario, I don't believe Roon goes back to the HDD to read the data for real-time playback (again, assuming Roon Core is not installed to that HDD).

No matter what drive solution you pick, make sure you have adequate backups. You can get a NAS unit with multiple drives, but even with that you should have an external drive backup that is not connected to your computer or network, in case of a virus or ransomware attack. Another copy should be kept off-site or in the cloud.

I used JRiver to rip all my CDs to FLAC files. They are stored on my desktop PC, but also backed up to a single-drive Buffalo NAS drive. All my streamers (Bluesound) are pointed to the NAS drive. I also have a copy on an external HD (disconnected from anything) and a copy in a cloud backup service.

I back up everything to an external SSD Drive. Very simple using the Innuos Sense app. Not that this stuff is hard. 

You can keep it simple and inexpensive.  A spinning hard drive connected to your Roon server will work just fine.  It is important, however, to have backup copies of your music someplace else.  Any hard drive, be it spinning or SDD can fail.

I rip and/or download new music onto a Mac computer and then copy the music files over my wireless network to a USB hard drive that is attached to my Roon server..  That way I have a backup of my music on the MAC, which is also backed up on the Cloud.