Sorry for reviving this threat, but i’m running against the same problem. Now here is my 2 cents.
The Seafile librarys are stored in the ‘Seafile_data’ folder on the seafile server, right?. So what if you move the Seafile_data folder to /mnt/NAS and make a symbolic link to the original location. This way you store everything on your mounted nas drive without corrupting the seafile server itself, since it is still able to read the data because of the symbolic link.
Hyped for your thoughts. greetings.