[Linux](EN) Check systemd log using journalctl

Briefly review about journalctl

Environment and Prerequisite

• Linux base system
• Bash shell(/bin/bash)

What is journalctl?

journalctl

• systemd log is called journal.
• journalctl query logs of systemd.

Examples

Basic Usage

• Use journalctl command with options

journalctl [OPTIONS...] [MATCHES...]

Example - Check end of journals with explanatory explanations(errors or events)

• Use -xe option

journalctl -xe

Example - Check specific unit journals

• Use -u option

journalctl -u [systemd unit name]

Example - Keep tracking journals

• Use -f option

journalctl -f

Reference

• https://en.wikipedia.org/wiki/Systemd
• https://wiki.archlinux.org/index.php/Systemd/Journal
• https://www.freedesktop.org/software/systemd/man/journalctl.html