foreach (@jet_macs) 
{
  ($mac2,$switch2) = split / /,$_;
  	if (-e "$switch2.cfg")
		{
		print "Datei existiert bereits!\n";
		}
	else
		{ 	
		open(OUT,">$switch2.cfg");
 		print OUT "show multiauth mac $mac2";
  		close(OUT);
		}

}