#TIL : Use journalctl to check system logs

Logging and Monitoring are important factor for system admin. Checking the log will help you have a closer look into the issue. One tool could help you will handy features is journalctl.

Here are simple options :

• -f : follow the log (tailf)
• -u [service] : filter to show only [service] logs
• --since=[date] : Show entries not older than the specified date
• --until=[date] : Show entries not newer than the specified date

Example :

$ sudo journalctl -u nginx.service
$ sudo journalctl -u nginx.service --since yesterday
$ sudo journalctl -u nginx.service --since "2018-01-01" --until today