[mrtg] Re: Data Collection Size Limitation?

Steve Shipway s.shipway at auckland.ac.nz
Tue May 9 23:44:20 MEST 2006

> http://img250.imageshack.us/my.php?image=router8qq.gif
> Between 00:00 and 04:00 you can see the problem.  The same 
> problem appears every day during the same approximate window 
> (during our really busy hours).  The interface is GigE and 
> I'm using an AbsMax of about 10Gb to make sure we're not 
> going beyond the bounds.

Looks very much like the old wrapping-counter problem.  If you use a 16-bit
counter for a fast link, then at about 130Mb/s or so the counter gets so big
that MRTG thinks it has wrapped around, hence you get this effect (I may be
a bit wrong with the numbers but thats it in a nutshell).

The solution is to use the SNMPv2 and 64bit high-speed counters for this
interface, then everything works.  Seen the same problem here, switched to
use 64bit, all now OK.


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

More information about the mrtg mailing list