Uploaded March 2022 | Updated September 2026, 2 weeks ago

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In this video we'll go through different log files in Debian and Fedora based distros like Ubuntu and RedHat. We'll also cover different commands that help viewing the log files.
#terminal #linux #logs #rockylinux #ubuntu #redhat
https://itvraag.nl

Timestamp:
0:00 Intro
0:19 my setup with Ubuntu & Rocky Linux VMs
0:40 log files path
0:55 list of log files
1:13 commands to view log files
1:35 cat syslog
2:38 less auth.log
3:15 tail dpkg.log (most recent)
3:50 head kern.log
4:21 watch auth.log (live logs)
4:48 grep logs (search pattern)
5:46 dmesg (diagnotic messages)
6:19 logger (custom logs entries to syslog)
6:48 journalctl
8:40 log priorities

Related video:
Bash #1 - basic concepts: youtu.be/C-HwzPVLo1c
Bash #4 - variables: youtu.be/mOSnZ7zOF3g
Bash #6 - package manager APT: youtu.be/ZKPs-rnG6E0
Bash #7 - package manager DNF: youtu.be/T5QMnvHie0M
Vagrant #6 - Hyper-V: youtu.be/HNsdfTRfnig

Used commands:
hostnamectl
cd /var/log
sudo cat syslog
sudo less auth.log
sudo tail dpkg.log
sudo tail -5 dpkg.log
sudo head kern.log
sudo head -5 kern.log
sudo watch tail auth.log
sudo grep -i service syslog
sudo cat syslog | grep -i service
sudo tail kern.log | grep audit
sudo cat auth.log | grep failure
sudo dmesg
sudo dmesg | grep -i driver
sudo dmesg | grep -i usb
sudo dmesg --level=err,warn
sudo dmesg -T --level=err,warn
sudo dmesg --follow
sudo watch tail syslog
sudo logger adding a custom log entry for itvraag
sudo logger testing a new log entry by $USER on $(date)
journalctl
journalctl -r
journalctl -n 4
journalctl -fu ssh
journalctl --list-boots
journalctl -b 2
journalctl --since="2022-03-10 19:40:00"
journalctl --since "10 min ago"