Here’s an image of QJournalctl showing the journal entries of the current boot.
The journal stores a large amount of information. This can make it harder to find what you’re looking for. One of the most important features of journalctl is its filtering options. And QJournalctl lets you access that filtering. You can filter the entries by date / time, and by sysyslog identifiers.
The journal implements the standard syslog message levels. In order of highest to lowest priority, these are:
- 0: emergency
- 1: alert
- 2: critical
- 3: error
- 4: warning
- 5: notice
- 6: info
- 7: debug
These priority settings are accessed in QJournalctl with a simple slider.
While you will commonly want to display the information from the current boot, there are certainly times when previous boots are helpful. The journal can save information from many previous boots, so journalctl can be made to display information easily. And QJournalctl also offers the ability to display them.