"Why would you want to use an NBD rather than a more common file-sharing protocol? Several scenarios come to mind:
"If client can provide better tools for low-level maintenance of disks (newer versions of fsck, for instance) than the server, providing NBD access may make sense.
"The client may have need of expanded network disk space, but a traditional network filesystem may not be adequate. For instance, you might be testing new filesystem drivers or need features of a particular filesystem and those features might not be properly handled by NFS or SMB/CIFS.
"The server might not support the filesystem or data structures on the device you wish to export"
