Re: Consultants - FREE Zero Impact Sql & Service Level Monitor

devdev_at_my-deja.com wrote:

> "It does this on a separate box - the network must be configured such
> that it can see all the packets"
>
> Neil, don't you contradict yourself? Everything has some cost. Nothing
> comes for nothing.
>
> In article <8gcd21$r81$1_at_slb0.atl.mindspring.net>,
> "Mary Owens" <mowens_at_sqlpower.com> wrote:
> > Consultants - FREE Zero Impact Sql & Service Level Monitor
> > ==========================================================
> >
> > The database and service level monitor with ZERO impact wins!

The claim is zero impact -- not zero cost.

Since the ethernet is a CDMA (collision detect, multiple access) system, every computer on a network segment gets to hear every packet sent over the network. There is no impact on the computers being monitored if a third CPU also records the message -- that's what packet sniffers do.

So there is no impact on the monitored systems. There is a cost; you have to set up the third computer with the correct software and settings.

It is probably a trifle difficult to monitor loopback connections and definitely more than a trifle difficult to monitor shared memory or olipcstr connections -- they don't touch the network. But if the info goes over the network, it can be snooped by a suitable computer.

Unless, of course, you're using the CSS/CSM module to encrypt your messages...

--
Jonathan Leffler (jleffler_at_informix.com, jleffler_at_earthlink.net)
Guardian of DBD::Informix v1.00.PC1 -- see http://www.perl.com/CPAN
#include <disclaimer.h>