RE: Defcon Bill

Joe Barrera (joebar@microsoft.com)
Wed, 22 Apr 1998 12:36:51 -0700


> I fail to see a connexion between a file-system error and a total
> O.S. meltdown. Perhaps a better analogy would be "kernel panic".

Duh, well, "freeing free inode" is a fatal kernel panic.

Why do I get the bad feeling that I've forgotten more about Unix than most
of you know?

At any rate, when searching the web for information about panics, I found
the following book on Sun's recommended book list:

<http://www.sun.com/books/books/Drake/preface.html>
http://www.sun.com/books/books/Drake/preface.html

"The phone rings and you answer. A user says his terminal is dead. As soon
as you hang up, you receive another call and another complaint about no
response from the computer. Ignoring the next call, you get to the computer
console just in time to see the word 'Panic' scroll off the top of the
screen. Another message says something about 'dumping', and now the system
appears to be rebooting itself.

"What happened?

"UNIX systems 'panic'. It's a fact of life. Depending on the hardware and
software involved, some systems panic rather frequently, some once in a blue
moon, some never.

"What causes panics? What is happening when you see the 'dumping' message?
How can you find the source of troubles and get the system back on-line and
into working condition?
This book answers those questions and many more.

> Imagine if I tried to work on some piece of crap that you and your
> masters are pushing... I'd be dead in a week.

What an interesting theory -- one that clearly calls for an experiment. I'll
send a system out to you overnight.

- Joe

P.S. ObAmazonURL:

<li> <a
href="http://www.amazon.com/exec/obidos/ISBN=0131493868/forkrecommendedrA/">
Panic! : Unix System Crash Dump Analysis</a> by Chris Drake, Kimberely
Brown.

Joseph S. Barrera III <joebar@acm.org>
<http://research.microsoft.com/~joebar/>
Phone, Office: (415) 778-8227; Cellular: (415) 601-3719; Home: (650)
588-4801
The opinions expressed in this message are my own personal views and do not
reflect the official views of Microsoft Corporation.

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