foreach $machine (@machine_name) {
   $cmd = "$drone_ssh";
   {
      local $ssh;
      my %params;
      $params{"protocol"}    = '2,1';
      $params{"debug"}    = '1';
      $ssh = Net::SSH::Perl->new( "$machine", %params );
      $ssh->login("$drone_user", %params);
      ( $stdout, $stderr, $exit ) = $ssh->cmd($cmd);
      undef $ssh;
   }

   if ( $exit == 0 ) {
      {
         # copy run files to drone
         local $scp;
         $scp = Net::SCP->new( "$machine", "$drone_user" );
         foreach $filename (@files) {
            chomp( $target = $filename );
            $scp->put( "$target", 
                       "$base_directory\/$work_directory\/" )
               || ( $scp->{errstr}
                 && print( $LF,
                         "ERROR: scp $target to $machine: $scp->{errstr}" )
            ); 
         }
         undef $scp;
      }
   }