diff --git a/railties/test/application/configuration_test.rb b/railties/test/application/configuration_test.rb
index 391139d7f8..f97be6e91d 100644
--- a/railties/test/application/configuration_test.rb
+++ b/railties/test/application/configuration_test.rb
@@ -967,6 +967,31 @@ module ApplicationTests
       end
     end
 
+    test "Not setting config.log_level is not deprecated for non-production environment" do
+      build_app
+      remove_from_config "config.log_level = .*"
+      with_rails_env "development" do
+        assert_not_deprecated(/log_level/) { require "#{app_path}/config/environment" }
+      end
+    end
+
+    test "Not setting config.log_level is deprecated for the production environment" do
+      build_app
+      remove_from_config "config.log_level = .*"
+      with_rails_env "production" do
+        assert_deprecated(/log_level/) { require "#{app_path}/config/environment" }
+      end
+    end
+
+    test "Setting config.log_level removes the deprecation warning" do
+      build_app
+      remove_from_config "config.log_level = .*"
+      add_to_env_config "production", "config.log_level = :info"
+      with_rails_env "production" do
+        assert_not_deprecated(/log_level/) { require "#{app_path}/config/environment" }
+      end
+    end
+
     test "config.log_level with custom logger" do
       make_basic_app do |app|
         app.config.logger = Logger.new(STDOUT)
diff --git a/railties/test/isolation/abstract_unit.rb b/railties/test/isolation/abstract_unit.rb
index cbd06a76f6..9ad0ec0d34 100644
--- a/railties/test/isolation/abstract_unit.rb
+++ b/railties/test/isolation/abstract_unit.rb
@@ -163,6 +163,7 @@ module TestHelpers
       app.secrets.secret_key_base = "3b7cd727ee24e8444053437c36cc66c4"
       app.config.session_store :cookie_store, key: "_myapp_session"
       app.config.active_support.deprecation = :log
+      app.config.active_support.test_order = :random
       app.config.log_level = :info
 
       yield app if block_given?