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, systemd.crash_chvt,
25 systemd.crash_shell, systemd.crash_reboot, systemd.confirm_spawn,
26 systemd.service_watchdogs, systemd.show_status, systemd.log_target=,
27 systemd.log_level=, systemd.log_location=, systemd.log_color,
28 systemd.default_standard_output=, systemd.default_standard_error=,
29 systemd.setenv=, systemd.machine_id=, systemd.unified_cgroup_hierarchy,
30 systemd.legacy_systemd_cgroup_controller
31 Parameters understood by the system and service manager to control
32 system behavior. For details, see systemd(1).
33 systemd.mask=, systemd.wants=, systemd.debug_shell
35 Additional parameters understood by systemd-debug-generator(8), to
36 mask or start specific units at boot, or invoke a debug shell on
37 tty9.
38 systemd.restore_state=
40 This parameter is understood by several system tools to control
41 whether or not they should restore system state from the previous
42 boot. For details, see systemd-backlight@.service(8) and systemd-
43 rfkill.service(8).
44 systemd.volatile=
46 This parameter controls whether the system shall boot up in
47 volatile mode. Takes a boolean argument, or the special value
48 "state". If false (the default), normal boot mode is selected, the
49 root directory and /var are mounted as specified on the kernel
50 command line or /etc/fstab, or otherwise configured. If true, full
51 state-less boot mode is selected. In this case the root directory
52 is mounted as volatile memory file system ("tmpfs"), and only /usr
53 is mounted from the file system configured as root device, in
54 read-only mode. This enables fully state-less boots were the
55 vendor-supplied OS is used as shipped, with only default
56 configuration and no stored state in effect, as /etc and /var (as
57 well as all other resources shipped in the root file system) are
58 reset at boot and lost on shutdown. If this setting is set to
59 "state" the root file system is mounted as usual, however /var is
60 mounted as a volatile memory file system ("tmpfs"), so that the
61 system boots up with the normal configuration applied, but all
62 state reset at boot and lost at shutdown. For details, see systemd-
63 volatile-root.service(8) and systemd-fstab-generator(8).
64 quiet
66 Parameter understood by both the kernel and the system and service
67 manager to control console log verbosity. For details, see
68 systemd(1).
69 debug
71 Parameter understood by both the kernel and the system and service
72 manager to control console log verbosity. For details, see
73 systemd(1).
74 -b, rd.emergency, emergency, rd.rescue, rescue, single, s, S, 1, 2, 3,
76 4, 5
77 Parameters understood by the system and service manager, as
78 compatibility and convenience options. For details, see systemd(1).
79 locale.LANG=, locale.LANGUAGE=, locale.LC_CTYPE=, locale.LC_NUMERIC=,
81 locale.LC_TIME=, locale.LC_COLLATE=, locale.LC_MONETARY=,
82 locale.LC_MESSAGES=, locale.LC_PAPER=, locale.LC_NAME=,
83 locale.LC_ADDRESS=, locale.LC_TELEPHONE=, locale.LC_MEASUREMENT=,
84 locale.LC_IDENTIFICATION=
85 Parameters understood by the system and service manager to control
86 locale and language settings. For details, see systemd(1).
87 fsck.mode=, fsck.repair=
89 Parameters understood by the file system checker services. For
90 details, see systemd-fsck@.service(8).
91 quotacheck.mode=
93 Parameter understood by the file quota checker service. For
94 details, see systemd-quotacheck.service(8).
95 systemd.journald.forward_to_syslog=, systemd.journald.forward_to_kmsg=,
97 systemd.journald.forward_to_console=, systemd.journald.forward_to_wall=
98 Parameters understood by the journal service. For details, see
99 systemd-journald.service(8).
100 vconsole.keymap=, vconsole.keymap_toggle=, vconsole.font=,
102 vconsole.font_map=, vconsole.font_unimap=
103 Parameters understood by the virtual console setup logic. For
104 details, see vconsole.conf(5).
105 udev.log_priority=, rd.udev.log_priority=, udev.children_max=,
107 rd.udev.children_max=, udev.exec_delay=, rd.udev.exec_delay=,
108 udev.event_timeout=, rd.udev.event_timeout=, net.ifnames=
109 Parameters understood by the device event managing daemon. For
110 details, see systemd-udevd.service(8).
111 plymouth.enable=
113 May be used to disable the Plymouth boot splash. For details, see
114 plymouth(8).
115 luks=, rd.luks=, luks.crypttab=, rd.luks.crypttab=, luks.name=,
117 rd.luks.name=, luks.uuid=, rd.luks.uuid=, luks.options=,
118 rd.luks.options=, luks.key=, rd.luks.key=
119 Configures the LUKS full-disk encryption logic at boot. For
120 details, see systemd-cryptsetup-generator(8).
121 fstab=, rd.fstab=
123 Configures the /etc/fstab logic at boot. For details, see systemd-
124 fstab-generator(8).
125 root=, rootfstype=, rootflags=, ro, rw
127 Configures the root file system and its file system type and mount
128 options, as well as whether it shall be mounted read-only or
129 read-writable initially. For details, see systemd-fstab-
130 generator(8).
131 mount.usr=, mount.usrfstype=, mount.usrflags=
133 Configures the /usr file system (if required) and its file system
134 type and mount options. For details, see systemd-fstab-
135 generator(8).
136 roothash=, systemd.verity=, rd.systemd.verity=,
138 systemd.verity_root_data=, systemd.verity_root_hash=
139 Configures the integrity protection root hash for the root file
140 system, and other related parameters. For details, see systemd-
141 veritysetup-generator(8).
142 systemd.gpt_auto=, rd.systemd.gpt_auto=
144 Configures whether GPT based partition auto-discovery shall be
145 attempted. For details, see systemd-gpt-auto-generator(8).
146 systemd.default_timeout_start_sec=
148 Overwrites the default start job timeout DefaultTimeoutStartSec= at
149 boot. For details, see systemd-system.conf(5).
150 systemd.watchdog_device=
152 Overwrites the watchdog device path WatchdogDevice=. For details,
153 see systemd-system.conf(5).
154 modules_load=, rd.modules_load=
156 Load a specific kernel module early at boot. For details, see
157 systemd-modules-load.service(8).
158 resume=
160 Enables resume from hibernation using the specified device. All
161 fstab(5)-like paths are supported. For details, see systemd-
162 hibernate-resume-generator(8).
163 systemd.firstboot=
165 Takes a boolean argument, defaults to on. If off, systemd-
166 firstboot.service(8) will not query the user for basic system
167 settings, even if the system boots up for the first time and the
168 relevant settings are not initialized yet.
169
171 systemd(1), bootparam(7), dracut.cmdline(7), systemd-debug-
172 generator(8), systemd-fsck@.service(8), systemd-quotacheck.service(8),
173 systemd-journald.service(8), systemd-vconsole-setup.service(8),
174 systemd-udevd.service(8), plymouth(8), systemd-cryptsetup-generator(8),
175 systemd-veritysetup-generator(8), systemd-fstab-generator(8), systemd-
176 gpt-auto-generator(8), systemd-volatile-root.service(8), systemd-
177 modules-load.service(8), systemd-backlight@.service(8), systemd-
178 rfkill.service(8), systemd-hibernate-resume-generator(8), systemd-
179 firstboot.service(8)
180
182 1. kernel-parameters.html
183 https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html
184systemd 239 KERNEL-COMMAND-LINE(7)