RE: Interesting Assertions on W2K Stability

["Joe Pluta" <joepluta@xxxxxxxxxxxxxxxxx>]

You're correct, Walden. 99%.  But definitely not 99.99%.  But that's
COMPLETE NETWORK downtime.  But let's use that to see how valid your
argument about aggregate uptime is.

Let's say, for argument, that there are only five servers for msn.com.  In
order to get an aggregate failure rate of 99% per your theoretical
calculations, you'd need a single-system uptime of about 60%.

(1 - ((1 - 99%) ^ 1/5)) = 60.2%

Yeah, them's some good numbers.  I LOVE numbers.  You can make them say
whatever you want, provided you don't mess up the beautiful calculation with
some ugly common sense.  (Note: the single-unit uptime percentage drops as
you add more servers to this equation.)

The truth is that, even if you have completely redundant systems, if your
system is crap, then you have completely redundant crap.  MSN didn't go down
because all of its servers coincidentally failed - it went down because W2K
isn't an enterprise level OS, and can't handle industrial strength
applications.  With too much load, unexpected things happen, and W2K, like
all the Windows products, becomes unstable.  In a failover environment, that
means that the load is then shifted to other machines, making them even MORE
overloaded, leading to catastrophic cascading failure.

Or, as Microsoft terms it, "routing problems".

Ah, but this is a silly and specious argument, and I tire of it.  If you
truly think ten W2K machines is equivalent to an AS/400, then you are
welcome to your opinion.  And I'll do my best to not entrust my mission
critical business to you.

Joe

> -----Original Message-----
> From: Walden H. Leverich
>
> Joe,
> Um, maybe my calculator is broken, it is made by Microsoft after
> all, but 87
> hours of downtime is 99% not 90%. 90% is 36.5 DAYS of downtime.
> 3.65 DAYS is
> 87 hours and that is 99% uptime. Any admin that has a machine
> down more that
> 87 hours in a year is in trouble.