wiki/_next/data/Ie9t5zutrXP6Of75Cb5xF/cli.journalctl.json

{"pageProps":{"metadata":{"date":"\"2021-05-20 23:07:39 +08:00\"","date_modified":"\"2021-09-01 22:39:16 +08:00\"","language":"en","source":""},"title":"Command line: journalctl","hast":{"type":"root","children":[{"type":"element","tagName":"nav","properties":{"className":"toc"},"children":[{"type":"element","tagName":"ol","properties":{"className":"toc-level toc-level-1"},"children":[{"type":"element","tagName":"li","data":{"hookArgs":[{"type":"element","tagName":"h1","properties":{"id":"options"},"children":[{"type":"text","value":"Options"}]}]},"properties":{"className":"toc-item toc-item-h1"},"children":[{"type":"element","tagName":"a","properties":{"className":"toc-link toc-link-h1","href":"/cli.journalctl#options"},"children":[{"type":"text","value":"Options"}]}]},{"type":"element","tagName":"li","data":{"hookArgs":[{"type":"element","tagName":"h1","properties":{"id":"examples"},"children":[{"type":"text","value":"Examples"}]}]},"properties":{"className":"toc-item 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the latest logs with helpful messages"}]}]},{"type":"element","tagName":"li","data":{"hookArgs":[{"type":"element","tagName":"h2","properties":{"id":"get-the-logs-of-a-service-unit-from-2-boots-ago"},"children":[{"type":"text","value":"Get the logs of a service unit from 2 boots ago"}]}]},"properties":{"className":"toc-item toc-item-h2"},"children":[{"type":"element","tagName":"a","properties":{"className":"toc-link toc-link-h2","href":"/cli.journalctl#get-the-logs-of-a-service-unit-from-2-boots-ago"},"children":[{"type":"text","value":"Get the logs of a service unit from 2 boots ago"}]}]}]}]}]}]},{"type":"element","tagName":"p","properties":{},"children":[{"type":"text","value":"The logging daemon of systemd (see "},{"type":"element","tagName":"a","properties":{"href":"/linux.systemd.journal"},"children":[{"type":"text","value":"systemd-journald"}]},{"type":"text","value":").\nNot only it can view your logs, you can ask to view specific logs and delete some of them.\n"}]},{"type":"element","tagName":"p","properties":{},"children":[{"type":"text","value":"For more information, see "},{"type":"element","tagName":"code","properties":{"className":["inline-verbatim"]},"children":[{"type":"text","value":"journalctl.1"}]},{"type":"text","value":" manual page.\n"}]},{"type":"element","tagName":"h1","properties":{"id":"options"},"children":[{"type":"text","value":"Options"}]},{"type":"element","tagName":"ul","properties":{},"children":[{"type":"element","tagName":"li","properties":{},"children":[{"type":"element","tagName":"p","properties":{},"children":[{"type":"element","tagName":"code","properties":{"className":["inline-verbatim"]},"children":[{"type":"text","value":"-b, --boot [ID][+OFFSET]"}]},{"type":"text","value":" shows the logs starting from given boot time (or current boot if empty).\n"}]}]},{"type":"element","tagName":"li","properties":{},"children":[{"type":"element","tagName":"p","properties":{},"children":[{"type":"element","tagName":"code","properties":{"className":["inline-verbatim"]},"children":[{"type":"text","value":"-e, --pager-end"}]},{"type":"text","value":" to go to the end of the logs.\n"}]}]},{"type":"element","tagName":"li","properties":{},"children":[{"type":"element","tagName":"p","properties":{},"children":[{"type":"element","tagName":"code","properties":{"className":["inline-verbatim"]},"children":[{"type":"text","value":"-f, --follow"}]},{"type":"text","value":" watches the logs.\n"}]}]},{"type":"element","tagName":"li","properties":{},"children":[{"type":"element","tagName":"p","properties":{},"children":[{"type":"element","tagName":"code","properties":{"className":["inline-verbatim"]},"children":[{"type":"text","value":"-k, --dmesg"}]},{"type":"text","value":" prints the logs from the kernel.\n"}]}]},{"type":"element","tagName":"li","properties":{},"children":[{"type":"element","tagName":"p","properties":{},"children":[{"type":"element","tagName":"code","properties":{"className":["inline-verbatim"]},"children":[{"type":"text","value":"--list-boots"}]},{"type":"text","value":" prints a list of boots useful for knowing the boot logs from "},{"type":"element","tagName":"code","properties":{"className":["inline-verbatim"]},"children":[{"type":"text","value":"-b"}]},{"type":"text","value":".\n"}]}]},{"type":"element","tagName":"li","properties":{},"children":[{"type":"element","tagName":"p","properties":{},"children":[{"type":"element","tagName":"code","properties":{"className":["inline-verbatim"]},"children":[{"type":"text","value":"--user-unit"}]},{"type":"text","value":" shows logs from a user unit.\n"}]}]},{"type":"element","tagName":"li","properties":{},"children":[{"type":"element","tagName":"p","properties":{},"children":[{"type":"element","tagName":"code","properties":{"className":["inline-verbatim"]},"children":[{"type":"text","value":"-u, --unit [UNIT]"}]},{"type":"text","value":" shows the logs of a system unit.\n"}]}]},{"type":"element","tagName":"li","properties":{},"children":[{"type":"element","tagName":"p","properties":{},"children":[{"type":"element","tagName":"code","properties":{"className":["inline-verbatim"]},"children":[{"type":"text","value":"--vacuum-time [TIMESPAN]"}]},{"type":"text","value":" deletes logs older than the specified timespan "},{"type":"text","value":".\n"}]}]},{"type":"element","tagName":"li","properties":{},"children":[{"type":"element","tagName":"p","properties":{},"children":[{"type":"element","tagName":"code","properties":{"className":["inline-verbatim"]},"children":[{"type":"text","value":"-x, --catalog"}]},{"type":"text","value":" 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