[RC5] [admin] Learn from others' mistakes...

Nathaniel Hang nhang at home.com
Thu Jan 15 13:02:26 EST 1998

David McNett wrote:

> The client ran just fine, unnoticed and chugging along for quite some time.
> It didn't interfere at all with the operation of the server and didn't
> affect any user processes.
> However, the file server developed some problems.  It started to lock up.
> Processes would hang.  The vendor was called in to honour the support

I just HAD to respond to this.  I think it should be noted that an
incorrectly set up system can cause this.  If the hardware was not set
up to perfection, it can take time and/or a skilled person who knows and
understands hardware to find and diagnose a hardware problem.  Most
computer vendors do NOT have "techs" who know how to do this.

A computer that was not assembled by a real professional will still
work.  And will look fine to the typical user.  However, there may be
slight incompatibilities in the mainboard, RAM, cache, and/or cards
within the computer.  In this case, the system will effectively run
99.99% of the time.  However, 99.99 is not 100.  The computer will often
possibly generate a wrong result from time to time.  Sometimes these
results are clearly out of range, and result in a crash, or
malfunction.  However, most of the time the answer is within a valid
range, and will be accepted.  So over time, the OS or program will
slowly accumulate more and more wrong answers until one day it'll just

I would imagine that this case is a result of this.

> and, upon discovery of the client believed that it had found the source
> of the server lockups.

This is utterly BS.  It's more of an excuse to the fact that the vendor
didn't do it right when they built the system.

> county will have to pay thousands of dollars to re-install the operating
> system and data files and a complete security audit will have to be

Lastly, I am suggesting to the admins or the person who wrote the FAQ to
include a brief summary of my explanation.  And also to add that the
cracking client uses IDLE CPU cycles.  However, in effect, the program
uses the CPU ALL the time, and will cause the system/CPU to generate
more heat/stress than a typical system.  Heat is the enemy of the
computer.  Heat will degrade the CPU over time (10 years).  Also,
incorrectly set-up Overclocked systems may/will also show strange
behaviour over time, even when the user may not notice it.  

The thing is that make it known that the client WILL cause strange
behaviour or problems if the computer isn't 100% perfect.  The reason
being that it increases the chance a wrong results pops up; which will
eventually lead to crashes/lock-up/etc.  In other words, the RC5/DES
client is a stress test for the computer.

If people really want to know if their system is 100% stable, then
request it on this list, otherwise, I'm not going to  answer it here. 
This message is getting long. ;)

-nathaniel hang

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