diff --git a/make-block.pl b/make-block.pl
index 64cebfb..f778e4d 100755
--- a/make-block.pl
+++ b/make-block.pl
@@ -72,10 +72,8 @@ MAIN: {
     my $workdir = $FindBin::RealBin;
 
     unless (GetOptions(
-        'out=s' => \$out,
-        'O=s' => \$out,
-        'i=s' => \$block_ip,
-        'block-ip=s' => \$block_ip,
+        'out|O=s' => \$out,
+        'block-ip|i=s' => \$block_ip,
     )) {
         exit 2;
     }