See, that is why Redhat and Mr. Poettering have introduced all in one systemd command that does grep and limiting output in a single go for a given service log. How cool is that? You guys hate systemd for no good reason 🤭
```
journalctl -u nginx.service -g failed -n 10
```
Also see Linux file log and how to access them https://www.cyberciti.biz/faq/linux-log-files-location-and-how-do-i-view-logs-files/ for more info