{
    "mode": "man",
    "parameter": "systemd-sysctl",
    "section": "8",
    "url": "https://www.chedong.com/phpMan.php/man/systemd-sysctl/8/json",
    "generated": "2026-10-06T12:40:15Z",
    "synopsis": "/usr/lib/systemd/systemd-sysctl [OPTIONS...] [CONFIGFILE...]\nsystemd-sysctl.service",
    "sections": {
        "NAME": {
            "content": "systemd-sysctl.service, systemd-sysctl - Configure kernel parameters at boot\n",
            "subsections": []
        },
        "SYNOPSIS": {
            "content": "/usr/lib/systemd/systemd-sysctl [OPTIONS...] [CONFIGFILE...]\n\nsystemd-sysctl.service\n",
            "subsections": []
        },
        "DESCRIPTION": {
            "content": "systemd-sysctl.service is an early boot service that configures sysctl(8) kernel parameters\nby invoking /usr/lib/systemd/systemd-sysctl.\n\nWhen invoked with no arguments, /usr/lib/systemd/systemd-sysctl applies all directives from\nconfiguration files listed in sysctl.d(5). If one or more filenames are passed on the command\nline, only the directives in these files are applied.\n\nIn addition, --prefix= option may be used to limit which sysctl settings are applied.\n\nSee sysctl.d(5) for information about the configuration of sysctl settings. After sysctl\nconfiguration is changed on disk, it must be written to the files in /proc/sys/ before it\ntakes effect. It is possible to update specific settings, or simply to reload all\nconfiguration, see Examples below.\n",
            "subsections": []
        },
        "OPTIONS": {
            "content": "",
            "subsections": [
                {
                    "name": "--prefix=",
                    "content": "Only apply rules with the specified prefix.\n\nAdded in version 230.\n"
                },
                {
                    "name": "--strict=",
                    "content": "Always return non-zero exit code on failure (including invalid sysctl variable name and\ninsufficient permissions), unless the sysctl variable name is prefixed with a \"-\"\ncharacter.\n\nAdded in version 252.\n"
                },
                {
                    "name": "--cat-config",
                    "content": "Copy the contents of config files to standard output. Before each file, the filename is\nprinted as a comment.\n",
                    "long": "--cat-config"
                },
                {
                    "name": "--tldr",
                    "content": "Copy the contents of config files to standard output. Only the \"interesting\" parts of the\nconfiguration files are printed, comments and empty lines are skipped. Before each file,\nthe filename is printed as a comment.\n",
                    "long": "--tldr"
                },
                {
                    "name": "--no-pager",
                    "content": "Do not pipe output into a pager.\n",
                    "long": "--no-pager"
                },
                {
                    "name": "-h --help",
                    "content": "Print a short help text and exit.\n",
                    "flag": "-h",
                    "long": "--help"
                },
                {
                    "name": "--version",
                    "content": "Print a short version string and exit.\n",
                    "long": "--version"
                }
            ]
        },
        "CREDENTIALS": {
            "content": "systemd-sysctl supports the service credentials logic as implemented by\nImportCredential=/LoadCredential=/SetCredential= (see systemd.exec(5) for details). The\nfollowing credentials are used when passed in:\n\nsysctl.extra\nThe contents of this credential may contain additional lines to operate on. The\ncredential contents should follow the same format as any other sysctl.d/ drop-in\nconfiguration file. If this credential is passed it is processed after all of the drop-in\nfiles read from the file system. The settings configured in the credential hence take\nprecedence over those in the file system.\n\nAdded in version 252.\n\nNote that by default the systemd-sysctl.service unit file is set up to inherit the\n\"sysctl.extra\" credential from the service manager.\n",
            "subsections": []
        },
        "EXAMPLES": {
            "content": "",
            "subsections": [
                {
                    "name": "Example 1. Reset all sysctl settings",
                    "content": "systemctl restart systemd-sysctl\n"
                },
                {
                    "name": "Example 2. View coredump handler configuration",
                    "content": "# sysctl kernel.corepattern\nkernel.corepattern = |/usr/libexec/abrt-hook-ccpp %s %c %p %u %g %t %P %I\n"
                },
                {
                    "name": "Example 3. Update coredump handler configuration",
                    "content": "# /usr/lib/systemd/systemd-sysctl --prefix kernel.corepattern\n\nThis searches all the directories listed in sysctl.d(5) for configuration files and writes\n/proc/sys/kernel/corepattern.\n"
                },
                {
                    "name": "Example 4. Update coredump handler configuration according to a specific file",
                    "content": "# /usr/lib/systemd/systemd-sysctl 50-coredump.conf\n\nThis applies all the settings found in 50-coredump.conf. Either\n/etc/sysctl.d/50-coredump.conf, or /run/sysctl.d/50-coredump.conf, or\n/usr/lib/sysctl.d/50-coredump.conf will be used, in the order of preference.\n\nSee sysctl(8) for various ways to directly apply sysctl settings.\n"
                }
            ]
        },
        "SEE ALSO": {
            "content": "systemd(1), sysctl.d(5), sysctl(8)\n\nsystemd 255                                                                SYSTEMD-SYSCTL.SERVICE(8)",
            "subsections": []
        }
    },
    "summary": "systemd-sysctl.service, systemd-sysctl - Configure kernel parameters at boot",
    "flags": [
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Only apply rules with the specified prefix. Added in version 230."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Always return non-zero exit code on failure (including invalid sysctl variable name and insufficient permissions), unless the sysctl variable name is prefixed with a \"-\" character. Added in version 252."
        },
        {
            "flag": "",
            "long": "--cat-config",
            "arg": null,
            "description": "Copy the contents of config files to standard output. Before each file, the filename is printed as a comment."
        },
        {
            "flag": "",
            "long": "--tldr",
            "arg": null,
            "description": "Copy the contents of config files to standard output. Only the \"interesting\" parts of the configuration files are printed, comments and empty lines are skipped. Before each file, the filename is printed as a comment."
        },
        {
            "flag": "",
            "long": "--no-pager",
            "arg": null,
            "description": "Do not pipe output into a pager."
        },
        {
            "flag": "-h",
            "long": "--help",
            "arg": null,
            "description": "Print a short help text and exit."
        },
        {
            "flag": "",
            "long": "--version",
            "arg": null,
            "description": "Print a short version string and exit."
        }
    ],
    "examples": [
        "systemctl restart systemd-sysctl",
        "# sysctl kernel.corepattern",
        "kernel.corepattern = |/usr/libexec/abrt-hook-ccpp %s %c %p %u %g %t %P %I",
        "# /usr/lib/systemd/systemd-sysctl --prefix kernel.corepattern",
        "This searches all the directories listed in sysctl.d(5) for configuration files and writes",
        "/proc/sys/kernel/corepattern.",
        "# /usr/lib/systemd/systemd-sysctl 50-coredump.conf",
        "This applies all the settings found in 50-coredump.conf. Either",
        "/etc/sysctl.d/50-coredump.conf, or /run/sysctl.d/50-coredump.conf, or",
        "/usr/lib/sysctl.d/50-coredump.conf will be used, in the order of preference.",
        "See sysctl(8) for various ways to directly apply sysctl settings."
    ],
    "see_also": [
        {
            "name": "systemd",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/systemd/1/json"
        },
        {
            "name": "sysctl.d",
            "section": "5",
            "url": "https://www.chedong.com/phpMan.php/man/sysctl.d/5/json"
        },
        {
            "name": "sysctl",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/sysctl/8/json"
        },
        {
            "name": "SYSTEMD-SYSCTL.SERVICE",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/SYSTEMD-SYSCTL.SERVICE/8/json"
        }
    ]
}