[mrtg] Re: Math

Alex van den Bogaerdt alex at slot.hollandcasino.nl
Fri Feb 11 22:33:40 MET 2000

Daniel R . Kilbourne wrote:
> On Fri, Feb 11, 2000 at 02:03:19PM -0500, Bryan Socha wrote:
> > Is it just me or does subtracting interfaces/oid not work?  Addition is
> > excellent but does anyone know anything about this?
> > 
> Well, I've never tried it, but you could always add the inverse

Nope, the inverse would be adding "-1:public at device" which is, for MRTG,
the same as swapping in and out for interface 1 and adding that to the
other interface.  This means that a simple sum like:
   "2:public at device + -1:public at device"
may verywell be the same as adding interface 1 output to interface 2
input and vice versa.

Perhaps the following will subtract: (mind the spaces around the '-')
   "2:public at device - 1:public at device"
(never tried it but if I would like to try it, this is how I would go).

If anything else fails, you can always use the external program interface
and do it yourself.

Another option would be to use rrdtool.

 / 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 |

Unsubscribe mailto:mrtg-request at list.ee.ethz.ch?subject=unsubscribe
Help        mailto:mrtg-request at list.ee.ethz.ch?subject=help
Archive     http://www.ee.ethz.ch/~slist/mrtg

More information about the mrtg mailing list