How To Use Journalctl to View and Manipulate Systemd Logs

If you are using a Linux system with Systemd as the init system, you may want to view and manipulate the logs generated by Systemd using the journalctl utility. In this tutorial, we will guide you on how to use journalctl to view and manipulate Systemd logs.

Step 1: Launch the Terminal

Open the terminal application on your Linux system.

Step 2: View Systemd Logs

To view the Systemd logs, run the following command:

sudo journalctl

This will display the Systemd logs in the terminal. You can use the arrow keys to scroll up and down the logs.

Step 3: Filter Logs by Unit

You can filter the logs by unit. For example, to view the logs for the sshd service, run the following command:

sudo journalctl -u sshd

This will display only the logs for the sshd service.

Step 4: Filter Logs by Time Range

You can filter the logs by time range. For example, to view the logs for the last hour, run the following command:

sudo journalctl --since "1 hour ago"

This will display only the logs generated in the last hour.

Step 5: Filter Logs by Keyword

You can filter the logs by keyword. For example, to view the logs containing the keyword "error", run the following command:

sudo journalctl -k error

This will display only the logs containing the keyword "error".

Step 6: Save Logs to a File

You can save the logs to a file. For example, to save the logs for the sshd service to a file named "sshd.log", run the following command:

sudo journalctl -u sshd > sshd.log

This will save the logs for the sshd service to a file named "sshd.log".

Conclusion

Using the journalctl utility, you can easily view and manipulate the Systemd logs on your Linux system. You can filter the logs by unit, time range, and keyword, and save the logs to a file.

Keywords: Journalctl, Systemd Logs, Linux, Terminal Commands, Filter Logs, Keyword, Time Range, Save Logs to File.