# mount -t nfs 127.0.0.1:/exports/plop1 /mnt/nfs
mount.nfs: access denied by server while mounting 127.0.0.1:/exports/plop1

# chmod 1777 /exports/plop1
# chmod 1777 /exports
# mount -t nfs 127.0.0.1:/exports/plop1 /mnt/nfs