diff --git a/lib/kadeploy3/server/parallel_ops.rb b/lib/kadeploy3/server/parallel_ops.rb
index bca67b7f8c26028f8be093995baad0a024743ad0..64a3c3049c3ffc97dae2b63743c53558a5608578 100644
--- a/lib/kadeploy3/server/parallel_ops.rb
+++ b/lib/kadeploy3/server/parallel_ops.rb
@@ -51,7 +51,7 @@ module Kadeploy
 
       res = nil
       takbin = nil
-      takargs = nil
+      takargs = []
       stderr = nil
       do_taktuk do |tak|
         tak.broadcast_exec[command]