[mrtg] Re: clearing of counters on Cisco

[Sander Foppen]

I also had problems with spikes in my graphs. These spikes didn't
necessarily occurred when the counters where cleared but also when a
router couldn't be reached for a wile. When the connection came back a
spike was visible. It seemed like wile there was no management
connection with the router the counters kept counting. When the
management connection came back the difference between the last known
counter and the new counter was calculated as displayed as the value for
the period of now and 5 min ago in stead of now and the last time there
was a management connection.

I fixed this problem using interface descriptions in stead of index
numbers to identify the interfaces.

If anyone thinks my reasoning above is false please notify my.

Gr, 
  Sander Foppen

-----Original Message-----
From: mrtg-bounce at list.ee.ethz.ch [mailto:mrtg-bounce at list.ee.ethz.ch]
On Behalf Of Scott P. Daffron
Sent: vrijdag 24 januari 2003 17:26
To: mrtg at list.ee.ethz.ch
Subject: [mrtg] clearing of counters on Cisco


Oh most wise MRTG gurus,

We have noticed that our version of MRTG (a couple years old) shows a
huge
spike on our Cisco interface graphs whenever a "clear counters" is done
on
the device.  This is becoming a big problem for us, as we have just
implemented a new NMS which clears all counters once per day.

I know this is an issue of the OID counter wrapping, leading MRTG to
think
that a massive bandwidth spike has indeed occurred, but is there a way
to
configure MRTG not to draw this conclusion (and alleviate all of the
massive spikes in our graphs)?  Does a newer version of MRTG handle this
differently?  I have looked high and low, but can't seem to find an
answer
on this.  Thanks in advance...


Scott Daffron
Network Engineer
Sentara Health Care



--
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

--
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