diff --git a/metadata/service/server/single.yml b/metadata/service/server/single.yml
index 0f2aef6..e3eaaa1 100644
--- a/metadata/service/server/single.yml
+++ b/metadata/service/server/single.yml
@@ -19,14 +19,14 @@
           servers:
             start: 5
             spare:
-              min: ${apache:server:mpm:servers:start}
+              min: ${apache:server:mpm:prefork:servers:start}
               max: 10
             # Avoid memory leakage by restarting workers every x requests
             max_requests: 0
           # Should be 80% of server memory / average memory usage of one worker
           max_clients: 150
           # Should be same or more than max clients
-          limit: ${apache:server:mpm:max_clients}
+          limit: ${apache:server:mpm:prefork:max_clients}
         event:
           enabled: false
         worker: