Opps. I did something stupid and now it won't boot. Or I forgot my password.
Does this mean another reinstall?


Lets start simple, you don't know root's password. Or you over customized and it won't boot.

At the LILO prompt you can give the kernel arguments "init=/bin/bash".
In lilo hit table, and you will see something like:
or vmlinux
or whatever
now type:
linux (or whatever you saw) init=/bin/bash.

Now you see a friendly:


Be careful. ctrl-alt-delete wil reboot inproperly.
if you try to jump ahead of me you will notice you can't write to the hard drive.

It's read only. To fix it:
mount -o remount /
(or /sbin/mount -o remount / if that fails)
Now you can write to the hard drive.
To fix roots password just do:
then to reboot:
umount /
Now ctrl-alt-delete or reboot or whatever, it's safe.

If say you were reading /etc/inittab and it said don't set the default run level to 6, so you do. Then just edit it again (don't try X, you'll have to use vi or something and change it back (3 is the usual).

For those wonder default run level 6 would be reboot as soon as it boots.

Once I wanted to use tcsh unstead of bash, but didn't know how to change it so in root's .bashrc i had:
But then i had to type exit<ENTER> exit<ENTER> to logout, so i put exit under tcsh. then something broke and tcsh didn't work, so i couldn't log in. Never fear! just edit .bashrc and fix it (the correct way to change shells running chsh).

Now lets say that didn't fix your problem, Lilo is screwed up or whatever.
Still you don't need to reinstall, but you will need the install cd, boot of it and at the prompt do:
linux root=/location/of/your/root/partition (like /dev/hda1)
then you should boot back to your linux install, and hopefully be able to fix the problem.

Even that won't work, LILO and your install have problems!
Install to another partition (swap maybe, you don't need swap, so just as a temp install) then after that boots, mount -t ext2 /location/of/root/partion (ex /dev/hda1) /mnt, now you can access all your files.

Good luck, and don't reinstall!