[mrtg] Re: A Theory...

Alex van den Bogaerdt alex at slot.hollandcasino.nl
Mon Aug 26 19:29:34 MEST 2002

Kevin S. Dome wrote:

> This may sound kind of off the wall but is it possible to have mrtg 
> ignore the traffic to/from certain ips? I do alot of 
> uploading/downloading from my laptop to my server while i am at work so 
> all the traffic shows up and seeing how its a network it shoots my 
> graphs insanely high so i am barely seeing the regular traffic, is it 
> possible to have mrtg (im assuming snmp) to ignore data going to/from my 
> laptop ip?

Sure this is possible.  MRTG doesn't know nor does it care about
your IP.

The only thing that matters is:  Are *you* capable of programming
*any* device that counts what you want it to count (nothing more
and nothing less) then make this counter available to MRTG.

If you can tell the router to count all traffic except the traffic
inbetween your laptop and your server, and if you can tell the router
to report this counter by means of SNMP then yes: MRTG probably can
use those numbers.

Again: MRTG knows nothing except what you tell it.  A normal MRTG
config is simply: "use the counter foo at device bar".  A normal
counter on device "bar" counts all traffic through interface "baz"
and makes this available in snmp-counter "foo".  If you change the
way your router counts traffic, you "automatically" change what MRTG

And no, I cannot tell you *how* to do this.  Even if you *would have*
told us what equipment you use, I probably cannot provide details.

Just a short pointer:  If you're monitoring a linux server with
ipchains installed (and you're somehow reporting its statistics
via SNMP) you can tell ipchains to do:

    allow traffic to/from "laptop"
    allow all traffic  and count it

This will result in a counter that sees all traffic except the
traffic from or to your laptop.  Now program your snmp daemon
to report the statistics from this specific counter.

Programming ipchains falls outside the scope of this list, so
does programming snmpd to provide the counter.  It is however
possible, no doubt about it.

 / alex at slot.hollandcasino.nl                  alex at ergens.op.het.net \
| work                                                         private |
| My employer is capable of speaking therefore I speak only for myself |
| Technical questions sent directly to me will be nuked. Use the list. | 
| http://faq.mrtg.org/                                                 |
| http://rrdtool.eu.org  --> tutorial                                  |

Unsubscribe mailto:mrtg-request at list.ee.ethz.ch?subject=unsubscribe
Archive     http://www.ee.ethz.ch/~slist/mrtg
FAQ         http://faq.mrtg.org    Homepage     http://www.mrtg.org
WebAdmin    http://www.ee.ethz.ch/~slist/lsg2.cgi

More information about the mrtg mailing list