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CompTIA Linux+ XK0-006 · Domain 5: Troubleshooting

Service failures: systemctl status exit codes, journalctl, dependencies, port conflicts

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Last reviewed September 30, 2026 · Leer en español

When a service will not start or keeps dying, the answer is almost always in its status and logs. A consistent routine resolves most failures quickly: read the status, then the logs, then test the configuration, then check dependencies, ports, permissions and resources. Linux+ questions often show a fragment of systemctl status output and ask what it means, so learn to read it precisely.

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