1KERNEL-COMMAND-LINE(7) kernel-command-line KERNEL-COMMAND-LINE(7)
2
6 kernel-command-line - Kernel command line parameters
7
9 /proc/cmdline
10
12 The kernel, the initial RAM disk (initrd) and basic userspace
13 functionality may be configured at boot via kernel command line
14 arguments.
15 For command line parameters understood by the kernel, please see
17 kernel-parameters.html[1] and bootparam(7).
18 For command line parameters understood by the initial RAM disk, please
20 see dracut.cmdline(7), or the documentation of the specific initrd
21 implementation of your installation.
22
24 systemd.unit=, rd.systemd.unit=, systemd.dump_core,
25 systemd.early_core_pattern=, systemd.crash_chvt, systemd.crash_shell,
26 systemd.crash_reboot, systemd.confirm_spawn, systemd.service_watchdogs,
27 systemd.show_status, systemd.log_target=, systemd.log_level=,
28 systemd.log_location=, systemd.log_color,
29 systemd.default_standard_output=, systemd.default_standard_error=,
30 systemd.setenv=, systemd.machine_id=, systemd.unified_cgroup_hierarchy,
31 systemd.legacy_systemd_cgroup_controller
32 Parameters understood by the system and service manager to control
33 system behavior. For details, see systemd(1).
34 systemd.mask=, systemd.wants=, systemd.debug_shell
36 Additional parameters understood by systemd-debug-generator(8), to
37 mask or start specific units at boot, or invoke a debug shell on
38 tty9.
39 systemd.run=, systemd.run_success_action=, systemd.run_failure_action=
41 Additional parameters understood by systemd-run-generator(8), to
42 run a command line specified on the kernel command line as system
43 service after booting up.
44 systemd.early_core_pattern=
46 During early boot, the generation of core dump files is disabled
47 until a core dump handler (if any) takes over. This parameter
48 allows to specifies an absolute path where core dump files should
49 be stored until a handler is installed. The path should be absolute
50 and may contain specifiers, see core(5) for details.
51 systemd.restore_state=
53 This parameter is understood by several system tools to control
54 whether or not they should restore system state from the previous
55 boot. For details, see systemd-backlight@.service(8) and systemd-
56 rfkill.service(8).
57 systemd.volatile=
59 This parameter controls whether the system shall boot up in
60 volatile mode. Takes a boolean argument, or the special value
61 "state". If false (the default), normal boot mode is selected, the
62 root directory and /var are mounted as specified on the kernel
63 command line or /etc/fstab, or otherwise configured. If true, full
64 state-less boot mode is selected. In this case the root directory
65 is mounted as volatile memory file system ("tmpfs"), and only /usr
66 is mounted from the file system configured as root device, in
67 read-only mode. This enables fully state-less boots were the
68 vendor-supplied OS is used as shipped, with only default
69 configuration and no stored state in effect, as /etc and /var (as
70 well as all other resources shipped in the root file system) are
71 reset at boot and lost on shutdown. If this setting is set to
72 "state" the root file system is mounted as usual, however /var is
73 mounted as a volatile memory file system ("tmpfs"), so that the
74 system boots up with the normal configuration applied, but all
75 state reset at boot and lost at shutdown. For details, see systemd-
76 volatile-root.service(8) and systemd-fstab-generator(8).
77 quiet
79 Parameter understood by both the kernel and the system and service
80 manager to control console log verbosity. For details, see
81 systemd(1).
82 debug
84 Parameter understood by both the kernel and the system and service
85 manager to control console log verbosity. For details, see
86 systemd(1).
87 -b, rd.emergency, emergency, rd.rescue, rescue, single, s, S, 1, 2, 3,
89 4, 5
90 Parameters understood by the system and service manager, as
91 compatibility and convenience options. For details, see systemd(1).
92 locale.LANG=, locale.LANGUAGE=, locale.LC_CTYPE=, locale.LC_NUMERIC=,
94 locale.LC_TIME=, locale.LC_COLLATE=, locale.LC_MONETARY=,
95 locale.LC_MESSAGES=, locale.LC_PAPER=, locale.LC_NAME=,
96 locale.LC_ADDRESS=, locale.LC_TELEPHONE=, locale.LC_MEASUREMENT=,
97 locale.LC_IDENTIFICATION=
98 Parameters understood by the system and service manager to control
99 locale and language settings. For details, see systemd(1).
100 fsck.mode=, fsck.repair=
102 Parameters understood by the file system checker services. For
103 details, see systemd-fsck@.service(8).
104 quotacheck.mode=
106 Parameter understood by the file quota checker service. For
107 details, see systemd-quotacheck.service(8).
108 systemd.journald.forward_to_syslog=, systemd.journald.forward_to_kmsg=,
110 systemd.journald.forward_to_console=, systemd.journald.forward_to_wall=
111 Parameters understood by the journal service. For details, see
112 systemd-journald.service(8).
113 vconsole.keymap=, vconsole.keymap_toggle=, vconsole.font=,
115 vconsole.font_map=, vconsole.font_unimap=
116 Parameters understood by the virtual console setup logic. For
117 details, see vconsole.conf(5).
118 udev.log_priority=, rd.udev.log_priority=, udev.children_max=,
120 rd.udev.children_max=, udev.exec_delay=, rd.udev.exec_delay=,
121 udev.event_timeout=, rd.udev.event_timeout=, net.ifnames=,
122 net.naming-scheme=
123 Parameters understood by the device event managing daemon. For
124 details, see systemd-udevd.service(8).
125 plymouth.enable=
127 May be used to disable the Plymouth boot splash. For details, see
128 plymouth(8).
129 luks=, rd.luks=, luks.crypttab=, rd.luks.crypttab=, luks.name=,
131 rd.luks.name=, luks.uuid=, rd.luks.uuid=, luks.options=,
132 rd.luks.options=, luks.key=, rd.luks.key=
133 Configures the LUKS full-disk encryption logic at boot. For
134 details, see systemd-cryptsetup-generator(8).
135 fstab=, rd.fstab=
137 Configures the /etc/fstab logic at boot. For details, see systemd-
138 fstab-generator(8).
139 root=, rootfstype=, rootflags=, ro, rw
141 Configures the root file system and its file system type and mount
142 options, as well as whether it shall be mounted read-only or
143 read-writable initially. For details, see systemd-fstab-
144 generator(8).
145 mount.usr=, mount.usrfstype=, mount.usrflags=
147 Configures the /usr file system (if required) and its file system
148 type and mount options. For details, see systemd-fstab-
149 generator(8).
150 roothash=, systemd.verity=, rd.systemd.verity=,
152 systemd.verity_root_data=, systemd.verity_root_hash=
153 Configures the integrity protection root hash for the root file
154 system, and other related parameters. For details, see systemd-
155 veritysetup-generator(8).
156 systemd.gpt_auto=, rd.systemd.gpt_auto=
158 Configures whether GPT based partition auto-discovery shall be
159 attempted. For details, see systemd-gpt-auto-generator(8).
160 systemd.default_timeout_start_sec=
162 Overwrites the default start job timeout DefaultTimeoutStartSec= at
163 boot. For details, see systemd-system.conf(5).
164 systemd.watchdog_device=
166 Overwrites the watchdog device path WatchdogDevice=. For details,
167 see systemd-system.conf(5).
168 modules_load=, rd.modules_load=
170 Load a specific kernel module early at boot. For details, see
171 systemd-modules-load.service(8).
172 resume=
174 Enables resume from hibernation using the specified device. All
175 fstab(5)-like paths are supported. For details, see systemd-
176 hibernate-resume-generator(8).
177 systemd.firstboot=
179 Takes a boolean argument, defaults to on. If off, systemd-
180 firstboot.service(8) will not query the user for basic system
181 settings, even if the system boots up for the first time and the
182 relevant settings are not initialized yet.
183
185 systemd(1), systemd-system.conf(5), bootparam(7), dracut.cmdline(7),
186 systemd-debug-generator(8), systemd-fsck@.service(8), systemd-
187 quotacheck.service(8), systemd-journald.service(8), systemd-vconsole-
188 setup.service(8), systemd-udevd.service(8), plymouth(8), systemd-
189 cryptsetup-generator(8), systemd-veritysetup-generator(8), systemd-
190 fstab-generator(8), systemd-gpt-auto-generator(8), systemd-volatile-
191 root.service(8), systemd-modules-load.service(8), systemd-
192 backlight@.service(8), systemd-rfkill.service(8), systemd-hibernate-
193 resume-generator(8), systemd-firstboot.service(8)
194
196 1. kernel-parameters.html
197 https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html
198systemd 241 KERNEL-COMMAND-LINE(7)