Re: Breaking in from the monitor at the console

[barnett () alydar crd ge com (Bruce Barnett)]

> Secondly, you may not even need the password. On older systems it often seems
> that you can use L1-A during bootup and then not require the password. On
> later systems this is fixed - you always need the password.


Just a note for historical accuracy. We tried to fix this problem on
early Sun's by adding a password checking step in /.profile (which is
only read when the system is booting.)


Some suggested a simple addition of a "login root" line to the
/.profile file. DON'T DO THIS! We had a system that had a disk problem,
crashed, rebooted into single user mode waiting for someone to run
FSCK.  The login program timed out, and terminated. This caused the
system to go into mutil-user boot without fixing the disk, which
corrupted the disk some more, which caused more reboots, etc.

Instead, we used a simple program that read the password file, 
and would not exit until the root password was typed correctly.

So there was a semi-fix for older systems, but I have heard that people
could still halt the system, change the kernel, and continue without
needing a password. I never knew how to do this.