Elasticsearch + Debian 11 | tweak the server

Set ulimit -n: Edit /etc/profile and add ulimit -n 65535 Disable swapping by removing all swap lines from your fstab. As an alternative add the following line to your elasticsearch.yml: bootstrap.memory_lock: true Then test it using the famous Kibana (DevTools) Console: GET _nodes?filter_path=**.mlockall It should return true. Do not tune the java dns timeouts.