How to restart NFS server on Ubuntu

  Once you set up your NFS exports by adding lines to /etc/exports you need to restart your NFS server; do this with the following:  
sudo /etc/init.d/nfs-kernel-server restart
  You should see output along the lines of:
 * Stopping NFS kernel daemon                 [ OK ] * Unexporting directories for NFS kernel daemon…           [ OK ] * Exporting directories for NFS kernel daemon… exportfs: /etc/exports [1]: Neither ‘subtree_check’ or ‘no_subtree_check’ specified for export “”. Assuming default behaviour (‘no_subtree_check’). NOTE: this default has changed since nfs-utils version 1.0.x
  Assuming no error messages pop up here you should now try to connect to your NFS share.