The "–vacuum-time" option in the journalctl command is used to specify the time measure for deleting Linux system logs. This option allows the system administrator to control the retention policy of the logs and manage the disk space effectively. By specifying the time measure, you can determine how long the logs should be retained before they are deleted.
When using the "–vacuum-time" option, you need to provide a time value followed by a time unit to specify the duration. The time value can be any positive integer, and the time unit can be one of the following: "s" for seconds, "m" for minutes, "h" for hours, "d" for days, "w" for weeks, "mo" for months, or "y" for years.
For example, if you want to delete logs that are older than 30 days, you would use the following command:
journalctl --vacuum-time=30d
This command will delete all logs that are older than 30 days, freeing up disk space on the system. Similarly, if you want to delete logs that are older than 1 year, you would use the following command:
journalctl --vacuum-time=1y
By specifying the time measure with the "–vacuum-time" option, you can automate the deletion of old logs and ensure that the system does not run out of disk space. It is important to note that deleting logs should be done with caution, as logs are valuable for troubleshooting and forensic analysis in the event of a security incident.
The "–vacuum-time" option in the journalctl command allows you to specify the time measure for deleting Linux system logs. By providing a time value and a time unit, you can control the retention policy of the logs and manage disk space effectively.
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