NFS exports FUSE problem

It is a known problem since, at least 2003, but haven't been fixed so far.

A patch for fuse kernel modules is available here.

Discussion on FUSE list.

If you try to export FUSE file system over NFS, you would see error message in daemon.log like this:

Mar 2 13:49:46 235-194 mountd[3211]: authenticated mount request from nb:907 for /mnt/sdb3 (/mnt/sdb3)
Mar 2 13:49:46 235-194 mountd[3211]: getfh failed: Operation not permitted

To be able to export over NFS, a file system driver should implement export_operations functions.