This page is for those who prefer to limit the verbosity of their system to a strict minimum, either for aesthetics or other reasons. Following this guide will remove all text from the bootup process. Video demonstration
Kernel parameters
Change the kernel parameters using the configuration options of your boot loader, to include the following parameters:
quiet vga=current
vga=current is the kernel argument that avoid weird behaviours like FS#32309.
If you are still getting messages printed to the console, it may be dmesg sending you what it thinks are important messages. You can change the level at which these messages will be printed by using quiet loglevel=<level>, where <level> is any number between 0 and 7, where 0 is the most critical, and 7 is debug levels of printing.
quiet loglevel=3 vga=current
Note that this only seems to work if both quiet and loglevel=<level> are both used, and they must be in that order (quiet first). The loglevel parameter will only change that which is printed to the console, the levels of dmesg itself will not be affected and will still be available through the journal as well as dmesg. For more information, see the Documentation/kernel-parameters.txt file of the linux-docs package.
If you also want to stop systemd from printing its version number when booting, you should also append udev.log_level=3 to your kernel parameters. If systemd is used in an initramfs, append rd.udev.log_level=3 instead. See systemd-udevd.service(8) § KERNEL_COMMAND_LINE for details.
If you are using the systemd hook in the initramfs, you may get systemd messages during initramfs initialization. You can pass rd.systemd.show_status=false to disable them, or rd.systemd.show_status=auto to only suppress successful messages (so in case of errors you can still see them). Actually, auto is already passed to systemd.show_status=auto when quiet is used, however for some motive sometimes systemd inside initramfs does not get it. Below are the parameters that you need to pass to your kernel to get a completely clean boot with systemd in your initramfs:
quiet loglevel=3 rd.systemd.show_status=auto rd.udev.log_level=3
Also touch ~/.hushlogin to remove the Last login message.
Remove console cursor blinking
The console cursor at boot keeps blinking if you follow these instructions. This can be solved by passing vt.global_cursor_default=0 to the kernel [1].
To recover the cursor in the TTY, run:
# setterm -cursor on >> /etc/issue
sysctl
To hide any kernel messages from the console, add or modify the kernel.printk line according to [2]:
/etc/sysctl.d/20-quiet-printk.conf
kernel.printk = 3 3 3 3
agetty
To hide agetty printed issue and "login:" prompt line from the console[3], create a drop-in snippet for getty@tty1.service.
/etc/systemd/system/getty@tty1.service.d/skip-prompt.conf
[Service] ExecStart= ExecStart=-/usr/bin/agetty --skip-login --nonewline --noissue --autologin username --noclear %I $TERM
startx
To hide startx messages, you could redirect its output to /dev/null, in your .bash_profile like so:
$ [[ $(fgconsole 2>/dev/null) == 1 ]] && exec startx -- vt1 &> /dev/null
fsck
To hide fsck messages during boot, let systemd check the root filesystem. For this, replace udev hook with systemd:
HOOKS=( base systemd fsck ...)
in /etc/mkinitcpio.conf and regenerate the initramfs.
Now edit systemd-fsck-root.service and systemd-fsck@.service:
# systemctl edit --full systemd-fsck-root.service # systemctl edit --full systemd-fsck@.service
Configuring StandardOutput and StandardError like this:
(...) [Service] Type=oneshot RemainAfterExit=yes ExecStart=/usr/lib/systemd/systemd-fsck StandardOutput=null StandardError=journal+console TimeoutSec=0
See [4] for more info on the options you can pass to systemd-fsck - you can change how often the service will check (or not) your filesystems.
Make GRUB silent
To hide GRUB welcome and boot messages, you may install unofficial grub-silentAUR package.
After the installation, it is required to reinstall GRUB to necessary partition first.
Then, take an example as /etc/default/grub.silent, and make necessary changes to /etc/default/grub.
Below three lines are necessary:
GRUB_DEFAULT=0 GRUB_TIMEOUT=0 GRUB_RECORDFAIL_TIMEOUT=$GRUB_TIMEOUT
Lastly, regenerate grub.cfg file.
Retaining or disabling the vendor logo from BIOS
Modern UEFI systems display a vendor logo on boot until handing over control to the bootloader; e.g. Lenovo laptops display a bright red Lenovo logo. This vendor logo is typically blanked by the bootloader (if standard GRUB is used) or by the kernel.
To prevent the kernel from blanking the vendor logo, Linux 4.19 introduced a new configuration option FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER that retains the contents of the framebuffer until text needs to be printed on the framebuffer console. As of November 2018 (Linux 4.19.1), the official Arch Linux kernels are compiled with CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER=y.
When combined with a low loglevel (to prevent text from being printed), the vendor logo can be retained while the system is initialized. Note that GRUB in the standard configuration blanks the screen; consider using EFISTUB booting instead to boot directly into the kernel and thus leverage deferred takeover.
The kernel command line should use loglevel=3 or rd.udev.log_level=3 as mentioned above. Note that if you often receive Core temperature above threshold, cpu clock throttled messages in the kernel log, you need to use log level 2 to silence these at boot time. Alternatively, if you compile your own kernel, adjust the log level of the message in arch/x86/kernel/cpu/mcheck/therm_throt.c.
If you use Intel graphics, see also Intel graphics#Fastboot.
Further reading:
- Phoronix: Linux 4.19 Adds Deferred Console Takeover Support For FBDEV - Cleaner Boot Process
- Hans de Goede: Adding deferred fbcon console takeover to the Fedora kernels
Disabling deferred takeover
If the new behavior leads to issues, you can disable deferred takeover by using the fbcon=nodefer kernel parameter.
getty
A getty is the generic name for a program which manages a terminal line and its connected terminal. Its purpose is to protect the system from unauthorized access. Generally, each getty process is started by systemd and manages a single terminal line.
Installation
agetty is the default getty in Arch Linux, as part of the util-linux package. It modifies the TTY settings while waiting for a login so that the newlines are not translated to CR-LFs. This tends to cause a "staircase effect" for messages printed to the console. Agetty manages virtual consoles and six of these virtual consoles are provided by default in Arch Linux. They are usually accessible by pressing Ctrl+Alt+F1 through Ctrl+Alt+F6.
Alternatives include:
- mingetty — A minimal getty which allows automatic logins.
- fbgetty — A console getty like mingetty, which supports framebuffers.
- mgetty — A versatile program to handle all aspects of a modem under Unix.
Add additional virtual consoles
Open the file /etc/systemd/logind.conf and set the option NAutoVTs=6 to the number of virtual terminals that you want at boot.
If you wish to start one temporarily, you can start a getty service at the desired TTY by typing:
$ systemctl start getty@ttyN.service
Automatic login to virtual console
Configuration relies on systemd drop-in files to override the default parameters passed to agetty.
Configuration differs for virtual versus serial consoles. In most cases, you want to set up automatic login on a virtual console, (whose device name is ttyN, where N is a number). The configuration of automatic login for serial consoles will be slightly different. Device names of the serial consoles look like ttySN, where N is a number.
Virtual console
Edit the provided unit either manually by creating the following drop-in snippet, or by running systemctl edit getty@tty1 and pasting its content:
/etc/systemd/system/getty@tty1.service.d/override.conf
[Service] ExecStart= ExecStart=-/usr/bin/agetty --autologin username --noclear %I $TERM
If you do not want full automatic login, but also do not want to type your username, you can replace --autologin username with --skip-login --login-options username.
If you want to use a tty other than tty1, see systemd FAQ.
Serial console
Create the following file (and leading directories):
/etc/systemd/system/serial-getty@ttyS0.service.d/autologin.conf
[Service] ExecStart= ExecStart=-/usr/bin/agetty --autologin username -s %I 115200,38400,9600 vt102
Nspawn console
To configure auto-login for a systemd-nspawn container, override console-getty.service:
/etc/systemd/system/console-getty.service.d/override.conf
[Service] ExecStart= ExecStart=-/sbin/agetty --noclear --autologin username --keep-baud console 115200,38400,9600 $TERM
If machinectl login my-container method is used to access the container, also add --autologin username to container-getty@.service template that manages pts/[0-9] pseudo ttys:
/etc/systemd/system/container-getty@.service.d/override.conf
[Service] ExecStart= ExecStart=-/sbin/agetty --noclear --autologin username --keep-baud pts/%I 115200,38400,9600 $TERM
Prompt only the password for a default user in virtual console login
Getty can be used to login from a virtual console with a default user, typing the password but without needing to insert the username. For instance, to prompt the password for username on tty1:
/etc/systemd/system/getty@tty1.service.d/override.conf
[Service] ExecStart= ExecStart=-/sbin/agetty -n -o username %I
and then
# systemctl enable getty@tty1
Have boot messages stay on tty1
By default, Arch has the getty@tty1 service enabled. The service file already passes --noclear, which stops agetty from clearing the screen. However systemd clears the screen before starting it. To disable this behavior, create /etc/systemd/system/getty@tty1.service.d/noclear.conf:
/etc/systemd/system/getty@tty1.service.d/noclear.conf
[Service] TTYVTDisallocate=no
This overrides only TTYVTDisallocate for agetty on TTY1, and leaves the global service file /usr/lib/systemd/system/getty@.service untouched. See Systemd#Editing provided units.
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