I have been using Roon and an external hard drive for my library. I copied all my music to my NAS (i.e., it duplicates the hard drive). I also backed up my Roon metadata (about 50 Gb) and copied that to the NAS.
So now I added the NAS as a library. But after it rendered all the music, all of my dozens of hours of careful work getting titles, artists, etc. the way I want is gone. How do I get the metadata/settings/tags that I had for my music on the hard drive to migrate to the NAS and display things exactly as they were before?
The most important thing here is that Roon does not “see” two copies of the same files at the same time, as it would lead to re-importing the duplicates as new and not have your edits associated with them.
The Preserve edits guide touches upon this, but to clarify, you should disable the old location and then enable the new location so Roon can match up the existing database entries with the new location of the media.
It sounds like you already had both enabled at the same time and Roon re-imported the content already, so your best be here is to restore the backup you had and disable the old location + enable the new one:
Steps
If you are moving files between locations, drives, or machines, then it is best to avoid letting Roon see 2 copies of the same file at the same time:
In Roon’s Settings > Storage , disable all old storage folders that contain the files that are being relocated.
For performance reasons, if you are adding a large amount of music (1000’s of tracks), quit Roon (or stop RoonServer on Nucleus). The best experience will come from letting Roon look at the folders when the files have settled.
Move/Copy the files
If you stopped Roon in Step 2, start it again.
In Roon’s Settings > Storage , edit the folders disabled in step 1 and change the folder location and re-enable it.