code: func (nfsMounter *nfsMounter) CanMount() error {
  	exec := nfsMounter.plugin.host.GetExec(nfsMounter.plugin.GetPluginName())
  	switch runtime.GOOS {
  	case "linux":
  		if _, err := exec.Run("test", "-x", "/sbin/mount.nfs"); err != nil {
  			return fmt.Errorf("Required binary /sbin/mount.nfs is missing")
  		}
  		if _, err := exec.Run("test", "-x", "/sbin/mount.nfs4"); err != nil {
  			return fmt.Errorf("Required binary /sbin/mount.nfs4 is missing")
  		}
  		return nil
  	case "darwin":
  		if _, err := exec.Run("test", "-x", "/sbin/mount_nfs"); err != nil {
  			return fmt.Errorf("Required binary /sbin/mount_nfs is missing")
  		}
  	}
  	return nil
  }
docs: // Checks prior to mount operations to verify that the required components (binaries, etc.)
  // to mount the volume are available on the underlying node.
  // If not, it returns an error