Make service hardening part of the reasoning
Students often lose marks by describing service hardening without evaluating it. A better approach is to compare the expected behaviour with the observed behaviour, identify the security consequence, and justify the next control or investigative step. That sequence keeps the discussion specific to linux security.
Where possible, compare the expected state with the observed state. For linux security, that comparison gives the reader a clear basis for judging whether the control, configuration, artefact or result is acceptable.
Show why firewall configuration changes the conclusion
A strong linux security submission should do more than mention firewall configuration. It should explain why the concept matters in the specific scenario, what evidence supports the interpretation, and where the analysis has limits. This makes the work easier to assess because the reader can follow the reasoning rather than infer it from screenshots or definitions.
A useful discussion also acknowledges constraints. Time, available evidence, lab scope, legal boundaries and incomplete data can all limit what can be concluded about least privilege or systemd services.