Quick Tip

Master `journalctl` Time Filtering for Instant Log Insights

Challenge: You need to quickly review logs from a specific time period on your RHEL or Ubuntu system to troubleshoot an issue, but sifting through endless log entries is time-consuming.

The Solution: Utilize `journalctl`’s powerful time-based filtering options to pinpoint relevant log entries.

journalctl --since "2023-10-27 10:00:00" --until "2023-10-27 11:30:00"

Why it works: The `–since` and `–until` flags allow you to specify a precise start and end time (or relative times like “yesterday” or “1 hour ago”) to narrow down the `journalctl` output, making log analysis much more efficient.

Pro-Tip: Combine time filtering with other options like `-u` (unit) or `-p` (priority) for even more granular log inspection. For example: journalctl -u nginx --since "yesterday" -p err.

Linux Tips & Tricks | © ngelinux.com | 5/29/2026