From b750101eb236130cf056c675997decbac904cc49 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 17:35:18 +0200 Subject: Adding upstream version 252.22. Signed-off-by: Daniel Baumann --- man/kernel-command-line.xml | 602 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 602 insertions(+) create mode 100644 man/kernel-command-line.xml (limited to 'man/kernel-command-line.xml') diff --git a/man/kernel-command-line.xml b/man/kernel-command-line.xml new file mode 100644 index 0000000..2e60beb --- /dev/null +++ b/man/kernel-command-line.xml @@ -0,0 +1,602 @@ + + + + + + + + kernel-command-line + systemd + + + + kernel-command-line + 7 + + + + kernel-command-line + Kernel command line parameters + + + + /proc/cmdline + + + + Description + + The kernel, the programs running in the initrd and in the host system may be configured at boot via + kernel command line arguments. In addition, various systemd tools look at the EFI variable + SystemdOptions (if available). Both sources are combined, but the kernel command line + has higher priority. Please note that the EFI variable is only used by systemd tools, and is + ignored by the kernel and other user space tools, so it is not a replacement for the kernel + command line. + + For command line parameters understood by the kernel, please + see + kernel-parameters.html + and + bootparam7. + + For command line parameters understood by the initrd, see + dracut.cmdline7, + or the documentation of the specific initrd implementation of your + installation. + + + + Core OS Command Line Arguments + + + + systemd.unit= + rd.systemd.unit= + systemd.dump_core + systemd.crash_chvt + systemd.crash_shell + systemd.crash_reboot + systemd.confirm_spawn + systemd.service_watchdogs + systemd.show_status + systemd.status_unit_format= + systemd.log_target= + systemd.log_level= + systemd.log_location= + systemd.log_color + systemd.default_standard_output= + systemd.default_standard_error= + systemd.setenv= + systemd.machine_id= + systemd.set_credential= + systemd.import_credentials= + + Parameters understood by the system and service + manager to control system behavior. For details, see + systemd1. + + + + + systemd.mask= + systemd.wants= + systemd.debug_shell + + Additional parameters understood by + systemd-debug-generator8, + to mask or start specific units at boot, or invoke a debug + shell on tty9. + + + + + systemd.run= + systemd.run_success_action= + systemd.run_failure_action= + + Additional parameters understood by + systemd-run-generator8, to + run a command line specified on the kernel command line as system service after booting up. + + + + + systemd.early_core_pattern= + + During early boot, the generation of core dump files is disabled until a core dump handler (if any) + takes over. This parameter allows specifying an absolute path where core dump files should be stored until + a handler is installed. The path should be absolute and may contain specifiers, see + core5 for details. + + + + + systemd.restore_state= + + This parameter is understood by several system tools + to control whether or not they should restore system state + from the previous boot. For details, see + systemd-backlight@.service8 + and + systemd-rfkill.service8. + + + + + + systemd.volatile= + + This parameter controls whether the system shall boot up in volatile mode. Takes a boolean argument, or + the special value state. If false (the default), normal boot mode is selected, the root + directory and /var/ are mounted as specified on the kernel command line or + /etc/fstab, or otherwise configured. If true, full state-less boot mode is selected. In + this case the root directory is mounted as volatile memory file system (tmpfs), and only + /usr/ is mounted from the file system configured as root device, in read-only mode. This + enables fully state-less boots were the vendor-supplied OS is used as shipped, with only default + configuration and no stored state in effect, as /etc/ and /var/ (as + well as all other resources shipped in the root file system) are reset at boot and lost on shutdown. If this + setting is set to state the root file system is mounted read-only, however + /var/ is mounted as a volatile memory file system (tmpfs), so that the + system boots up with the normal configuration applied, but all state reset at boot and lost at shutdown. If + this setting is set to overlay the root file system is set up as + overlayfs mount combining the read-only root directory with a writable + tmpfs, so that no modifications are made to disk, but the file system may be modified + nonetheless with all changes being lost at reboot. For details, see + systemd-volatile-root.service8 + and + systemd-fstab-generator8. + + + + + quiet + + Parameter understood by both the kernel and the system + and service manager to control console log verbosity. For + details, see + systemd1. + + + + + debug + + Parameter understood by both the kernel and the system + and service manager to control console log verbosity. For + details, see + systemd1. + + + + + -b + rd.emergency + emergency + rd.rescue + rescue + single + s + S + 1 + 2 + 3 + 4 + 5 + + Parameters understood by the system and service + manager, as compatibility and convenience options. For details, see + systemd1. + + + + + locale.LANG= + locale.LANGUAGE= + locale.LC_CTYPE= + locale.LC_NUMERIC= + locale.LC_TIME= + locale.LC_COLLATE= + locale.LC_MONETARY= + locale.LC_MESSAGES= + locale.LC_PAPER= + locale.LC_NAME= + locale.LC_ADDRESS= + locale.LC_TELEPHONE= + locale.LC_MEASUREMENT= + locale.LC_IDENTIFICATION= + + Parameters understood by the system and service + manager to control locale and language settings. For + details, see + systemd1. + + + + + fsck.mode= + fsck.repair= + + + Parameters understood by the file system checker + services. For details, see + systemd-fsck@.service8. + + + + + quotacheck.mode= + + + Parameter understood by the file quota checker + service. For details, see + systemd-quotacheck.service8. + + + + + systemd.journald.forward_to_syslog= + systemd.journald.forward_to_kmsg= + systemd.journald.forward_to_console= + systemd.journald.forward_to_wall= + + + Parameters understood by the journal service. For + details, see + systemd-journald.service8. + + + + + vconsole.keymap= + vconsole.keymap_toggle= + vconsole.font= + vconsole.font_map= + vconsole.font_unimap= + + + Parameters understood by the virtual console setup logic. For details, see + vconsole.conf5. + + + + + udev.log_level= + rd.udev.log_level= + udev.children_max= + rd.udev.children_max= + udev.exec_delay= + rd.udev.exec_delay= + udev.event_timeout= + rd.udev.event_timeout= + udev.timeout_signal= + rd.udev.timeout_signal= + udev.blockdev_read_only + rd.udev.blockdev_read_only + net.ifnames= + net.naming-scheme= + + + Parameters understood by the device event managing + daemon. For details, see + systemd-udevd.service8. + + + + + plymouth.enable= + + + May be used to disable the Plymouth boot splash. For + details, see + plymouth8. + + + + + luks= + rd.luks= + luks.crypttab= + rd.luks.crypttab= + luks.name= + rd.luks.name= + luks.uuid= + rd.luks.uuid= + luks.options= + rd.luks.options= + luks.key= + rd.luks.key= + + + Configures the LUKS full-disk encryption logic at + boot. For details, see + systemd-cryptsetup-generator8. + + + + + fstab= + rd.fstab= + + + Configures the /etc/fstab logic + at boot. For details, see + systemd-fstab-generator8. + + + + + root= + rootfstype= + rootflags= + ro + rw + + + Configures the root file system and its file system + type and mount options, as well as whether it shall be + mounted read-only or read-write initially. For details, + see + systemd-fstab-generator8. + + + + + mount.usr= + mount.usrfstype= + mount.usrflags= + + + Configures the /usr file system (if required) and + its file system type and mount options. For details, see + systemd-fstab-generator8. + + + + + veritytab= + rd.veritytab= + roothash= + systemd.verity= + rd.systemd.verity= + systemd.verity_root_data= + systemd.verity_root_hash= + systemd.verity.root_options= + usrhash= + systemd.verity_usr_data= + systemd.verity_usr_hash= + systemd.verity_usr_options= + + Configures the integrity protection root hash for the root and /usr file systems, and other related + parameters. For details, see + systemd-veritysetup-generator8. + + + + + systemd.getty_auto= + + + Configures whether the serial-getty@.service will run. + For details, see + systemd-getty-generator8. + + + + + systemd.gpt_auto= + rd.systemd.gpt_auto= + + + Configures whether GPT based partition auto-discovery + shall be attempted. For details, see + systemd-gpt-auto-generator8. + + + + + systemd.default_timeout_start_sec= + + + Overrides the default start job timeout DefaultTimeoutStartSec= at + boot. For details, see + systemd-system.conf5. + + + + + systemd.watchdog_device= + + + Overrides the watchdog device path WatchdogDevice=. For details, see + systemd-system.conf5. + + + + + systemd.watchdog_sec= + + + Overrides the watchdog timeout settings otherwise configured with + RuntimeWatchdog=, RebootWatchdog= and + KExecWatchdogSec=. Takes a time value (if no unit is specified, seconds is the + implicitly assumed time unit) or the special strings off or + default. For details, see + systemd-system.conf5. + + + + + systemd.watchdog_pre_sec= + + + Overrides the watchdog pre-timeout settings otherwise configured with + RuntimeWatchdogPreSec=. Takes a time value (if no unit is specified, seconds is the + implicitly assumed time unit) or the special strings off or + default. For details, see + systemd-system.conf5. + + + + + systemd.watchdog_pretimeout_governor= + + + Overrides the watchdog pre-timeout settings otherwise configured with + RuntimeWatchdogPreGovernor=. Takes a string value. For details, see + systemd-system.conf5. + + + + + systemd.cpu_affinity= + + + Overrides the CPU affinity mask for the service manager and the default for all child + processes it forks. This takes precedence over CPUAffinity=, see + systemd-system.conf5 + for details. + + + + + modules_load= + rd.modules_load= + + + Load a specific kernel module early at boot. For + details, see + systemd-modules-load.service8. + + + + + resume= + resumeflags= + + + Enables resume from hibernation using the specified + device and mount options. All + fstab5-like + paths are supported. For details, see + systemd-hibernate-resume-generator8. + + + + + systemd.firstboot= + + Takes a boolean argument, defaults to on. If off, + systemd-firstboot.service8 + will not query the user for basic system settings, even if the system boots up for the first time and + the relevant settings are not initialized yet. Not to be confused with + systemd.condition-first-boot= (see below), which overrides the result of the + ConditionFirstBoot= unit file condition, and thus controls more than just + systemd-firstboot.service behaviour. + + + + systemd.condition-needs-update= + + Takes a boolean argument. If specified, overrides the result of + ConditionNeedsUpdate= unit condition checks. See + systemd.unit5 for + details. + + + + systemd.condition-first-boot= + + Takes a boolean argument. If specified, overrides the result of + ConditionFirstBoot= unit condition checks. See + systemd.unit5 for + details. Not to be confused with systemd.firstboot= which only controls behaviour + of the systemd-firstboot.service system service but has no effect on the + condition check (see above). + + + + systemd.clock-usec= + + Takes a decimal, numeric timestamp in µs since January 1st 1970, 00:00am, to set the + system clock to. The system time is set to the specified timestamp early during boot. It is not + propagated to the hardware clock (RTC). + + + + systemd.random-seed= + + Takes a base64 encoded random seed value to credit with full entropy to the kernel's + random pool during early service manager initialization. This option is useful in testing + environments where delays due to random pool initialization in entropy starved virtual machines shall + be avoided. + + Note that if this option is used the seed is accessible to unprivileged programs from + /proc/cmdline. This option is hence a security risk when used outside of test + systems, since the (possibly) only seed used for initialization of the kernel's entropy pool might be + easily acquired by unprivileged programs. + + It is recommended to pass 512 bytes of randomized data (as that matches the Linux kernel pool + size), which may be generated with a command like the following: + + dd if=/dev/urandom bs=512 count=1 status=none | base64 -w 0 + + Again: do not use this option outside of testing environments, it's a security risk elsewhere, + as secret key material derived from the entropy pool can possibly be reconstructed by unprivileged + programs. + + + + + systemd.hostname= + + Accepts a hostname to set during early boot. If specified takes precedence over what + is set in /etc/hostname. Note that this does not bar later runtime changes to + the hostname, it simply controls the initial hostname set during early boot. + + + + + + History + + + + systemd 252 + Kernel command-line arguments systemd.unified_cgroup_hierarchy + and systemd.legacy_systemd_cgroup_controller were deprecated. Please switch to + the unified cgroup hierarchy. + + + + + + See Also + + systemd1, + systemd-system.conf5, + bootparam7, + dracut.cmdline7, + systemd-debug-generator8, + systemd-fsck@.service8, + systemd-quotacheck.service8, + systemd-journald.service8, + systemd-vconsole-setup.service8, + systemd-udevd.service8, + plymouth8, + systemd-cryptsetup-generator8, + systemd-veritysetup-generator8, + systemd-fstab-generator8, + systemd-getty-generator8, + systemd-gpt-auto-generator8, + systemd-volatile-root.service8, + systemd-modules-load.service8, + systemd-backlight@.service8, + systemd-rfkill.service8, + systemd-hibernate-resume-generator8, + systemd-firstboot.service8, + bootctl1 + + + + -- cgit v1.2.3