Rescue Mode¶
Finit supports a rescue mode which is activated by the rescue option
on the kernel command line. See cmdline docs for how to
activate it.
This rescue mode can be disabled at configure time using:
configure --without-rescue
The rescue mode comes in two flavors; traditional and fallback.
Note
In this mode initctl will not work. Use the -f flag to force
reboot, shutdown, or poweroff.
Traditional¶
This is what most users expect. A very early maintenance login prompt,
served by the system sulogin program from util-linux, or BusyBox. If
that is not found in $PATH, the bundled /libexec/finit/sulogin
program is used instead. If a successful login is made, or if the user
exits (Ctrl-D), the rescue mode is ended and the system boots up
normally.
Warning
The bundled sulogin in Finit can at configure time be given another
user than the default (root). If the sulogin user does not have a
password, or the account is locked, the user is presented with a
prompt: "Press enter to enter maintenance mode.", which will open
up a root shell without prompting for password!
Fallback¶
If no sulogin program is found, Finit tries to bring up as much of its
own functionality as possible, yet limiting many aspects, meaning; no
network, no fsck of file systems in /etc/fstab, no /etc/rc.local,
no runparts, and most plugins are skipped (except those that provide
functionality for the condition subsystem).
Instead of reading /etc/finit.conf et al, system configuration is read
from /lib/finit/rescue.conf, which can be freely modified by the
system administrator.
The bundled default rescue.conf contains nothing more than:
runlevel 1
tty [12345] rescue
The tty has the rescue option set, which works similar to the board
bring-up tty option notty. The major difference being that sulogin
is started to query for root/admin password. If sulogin is not found,
rescue behaves like notty and gives a plain root shell prompt.
If Finit cannot find /lib/finit/rescue.conf it defaults to:
tty [12345] rescue
There is no way to exit the fallback rescue mode.