Difference between revisions of "Automatic login to virtual console"

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(With systemd: add instructions to disable getty@.service before enabling autologin@.service)
(all information available in getty via https://wiki.archlinux.org/index.php?title=Getty&diff=440522&oldid=440520)
 
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[[Category:Boot process]]
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#REDIRECT: [[Getty#Automatic_login_to_virtual_console]]
[[Category:Security]]
 
[[es:Automatic login to virtual console]]
 
[[it:Automatic login to virtual console]]
 
{{Article summary start}}
 
{{Article summary text|Describes how to automatically log in to a virtual console.}}
 
{{Article summary heading|Related}}
 
{{Article summary wiki|Display Manager}}
 
{{Article summary wiki|Start X at Login}}
 
{{Article summary end}}
 
 
 
This article describes how to automatically log in to a ''virtual console'' at the end of the [[boot process]]. This article only covers console log-ins; methods for starting an [[Xorg|X server]] are described in [[Start X at Boot]].
 
 
 
__TOC__
 
== With default init ==
 
 
 
=== Using agetty ===
 
This is the preferred (i.e. clean) method. Edit {{ic|/etc/inittab}} like this:
 
{{hc|/etc/inittab|
 
c1:2345:respawn:/sbin/agetty -a ''USERNAME'' -8 -s 38400 tty1 linux
 
c2:2345:respawn:/sbin/agetty -8 -s 38400 tty2 linux
 
c3:2345:respawn:/sbin/agetty -8 -s 38400 tty3 linux
 
c4:2345:respawn:/sbin/agetty -8 -s 38400 tty4 linux
 
c5:2345:respawn:/sbin/agetty -8 -s 38400 tty5 linux
 
c6:2345:respawn:/sbin/agetty -8 -s 38400 tty6 linux
 
}}
 
to automatically log in {{ic|''USERNAME''}} to the first console (tty1).
 
 
 
If you want your username to be used automatically without skipping the password prompt:
 
 
 
c1:2345:respawn:/sbin/agetty -a ''USERNAME'' -o "-- \u" -8 -s 38400 tty1 linux
 
 
 
=== Using mingetty ===
 
{{Note|Although a {{pkg|mingetty}} derivative, {{AUR|fgetty}} does not support the {{ic|--autologin}} parameter.}}
 
 
 
Alternatively, you can install the {{pkg|mingetty}} package from the [[Official Repositories|official repositories]]. Mingetty is designed to be a minimal [[getty]] and allows automatic log-ins:
 
{{hc|/etc/inittab|
 
c1:2345:respawn:/sbin/mingetty --autologin ''USERNAME'' tty1 linux
 
c2:2345:respawn:/sbin/agetty -8 -s 38400 tty2 linux
 
c3:2345:respawn:/sbin/agetty -8 -s 38400 tty3 linux
 
c4:2345:respawn:/sbin/agetty -8 -s 38400 tty4 linux
 
c5:2345:respawn:/sbin/agetty -8 -s 38400 tty5 linux
 
c6:2345:respawn:/sbin/agetty -8 -s 38400 tty6 linux
 
}}
 
 
 
Using the above methods, you will get a re-login loop when trying to log out. If you wish to only login at boot, use the following:
 
{{hc|/etc/inittab|
 
c2:2345:respawn:/sbin/agetty -8 -s 38400 tty2 linux
 
c3:2345:respawn:/sbin/agetty -8 -s 38400 tty3 linux
 
c4:2345:respawn:/sbin/agetty -8 -s 38400 tty4 linux
 
c5:2345:respawn:/sbin/agetty -8 -s 38400 tty5 linux
 
c6:2345:respawn:/sbin/agetty -8 -s 38400 tty6 linux
 
a1:2345:wait:/sbin/mingetty --autologin ''USERNAME'' tty1 linux
 
c1:2345:respawn:/sbin/agetty -8 -s 38400 tty1 linux
 
}}
 
 
 
=== Using a C login program ===
 
 
 
As an alternative, a C login program can be written:
 
 
 
{{hc|autologin.c|
 
#include <unistd.h>
 
 
 
int main(void) {
 
  execlp("login", "login", "-f", "''USERNAME''", NULL);
 
}
 
}}
 
 
 
Here, the C function {{Ic|execlp}} executes the command {{Ic|login -f ''USERNAME''}}.
 
 
 
The program must be compiled and copied to an appropriate location:
 
 
 
$ gcc -o autologin autologin.c
 
# cp autologin /usr/local/sbin/
 
 
 
Finally, tell {{ic|/etc/inittab}} to use it:
 
{{hc|/etc/inittab|
 
c1:2345:respawn:/sbin/agetty -n -l /usr/local/sbin/autologin -s 38400 tty1 linux
 
c2:2345:respawn:/sbin/agetty -8 -s 38400 tty2 linux
 
c3:2345:respawn:/sbin/agetty -8 -s 38400 tty3 linux
 
c4:2345:respawn:/sbin/agetty -8 -s 38400 tty4 linux
 
c5:2345:respawn:/sbin/agetty -8 -s 38400 tty5 linux
 
c6:2345:respawn:/sbin/agetty -8 -s 38400 tty6 linux
 
}}
 
 
 
== With systemd ==
 
Create a new service file similar to {{ic|getty@.service}} by copying it to {{ic|/etc/systemd/system/}}:
 
 
 
# cp /usr/lib/systemd/system/getty@.service /etc/systemd/system/autologin@.service
 
 
 
{{Note|{{ic|/etc/systemd/system/}} takes precedence over {{ic|/usr/lib/systemd/system/}}.}}
 
 
 
Once created you can link the new {{ic|autologin@.service}} to your chosen tty, e.g. {{ic|tty1}}, {{ic|tty2}}, [...] {{ic|tty8}}, etc, by specifying it as an alias in the {{ic|[Install]}} section of the unit file. Also, change the value of {{ic|ExecStart}} in {{ic|autologin@.service}}, to end up with something like this:
 
 
 
{{hc|/etc/systemd/system/autologin@.service|
 
2=[Service]
 
[...]
 
ExecStart&#61;-/sbin/agetty --noclear -a ''USERNAME'' %I 38400
 
[...]
 
[Install]
 
Alias=getty.target.wants/getty@''tty1''.service
 
}}
 
{{Tip|It is possible to change {{ic|1=Type=idle}} to {{ic|1=Type=simple}} and avoid delaying the execution of agetty until all jobs (state change requests to units) are completed. This option is more useful when [[Start X at Login|starting X automatically]]. See {{ic|man systemd.service}} for more info. {{Note|{{ic|1=Type=simple}} can cause systemd boot-up messages to pollute the login prompt.}}}}
 
 
 
For security reasons, you may also want to change {{ic|1=Restart=always}} to {{ic|1=Restart=no}}.
 
 
 
Finally, you need to disable the old getty@.service for the specified TTY and enable the new autologin@.service for the same TTY:
 
# systemctl daemon-reload
 
# systemctl disable getty@tty1.service
 
# systemctl enable autologin@tty1.service
 
# systemctl start autologin@tty1.service
 
 
 
{{Warning|If you are currently in an X session on the same TTY configured in the service file, starting autologin@tty''X''.service will kill your X server.}}
 
 
 
To avoid errors related to display-manager.service in dmesg, you should set the default target to multi-user instead of graphical:
 
# systemctl enable multi-user.target
 
(See also: [[Systemd#Change_default_runlevel.2Ftarget_to_boot_into|Change default runlevel/target to boot into]].)
 

Latest revision as of 12:48, 17 August 2016