What causes single user boot?

[news.andy@spiegl.de (Andy Spiegl)]

Hi!

I've got a webserver which is running constantly.  A few days ago
we had to reboot it, because of a SCSI problem with the JAZ drive.
(side note: can you imagine the load went up to 115 still growing!?)

Well, after the reboot the system stopped at the prompt:
Press Ctrl-D or give root password.

I wonder what could have caused this?  This is a huge problem,
because the computer is many kilometers away and administered
only over the net.  It was tedious to find someone up there to
resolve this.  That's why I would really like to find out what
caused this and how I can avoid it in the future.

BTW: running Hamm incl.all updates

Thanks a lot in advance for any hint or pointer!
 Andy.

-- 
 Andy Spiegl, University of Technology, Muenchen, Germany
 E-Mail: Andy@spiegl.de     URL: http://www.spiegl.de
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