diff --git a/lib/redmine-installer/redmine.rb b/lib/redmine-installer/redmine.rb
index 528da76..34de7eb 100644
--- a/lib/redmine-installer/redmine.rb
+++ b/lib/redmine-installer/redmine.rb
@@ -713,7 +713,7 @@ def load_database_dump
       end
 
       def without_env(*names)
-        backup = ENV.clone.to_hash
+        backup = ENV.to_h
         ENV.delete_if {|key, _| names.include?(key) }
         yield
       ensure