Why do you say it is wrong? This is exactly how it should be calculated. The ThreshMaxI and ThreshMaxO are computed based on the interval.
What is wrong about it? If MRTG polls in 5 minute intervals, the only threshold it knows about is the 5 minute window. If you want it to compute the thresholds on a lower interval (like 1 minute), you need to poll that often and set the threshold accordingly. How is MRTG supposed to alert you of a threshold that has been crossed at any one point during the interval? This is what you are asking for. MRTG is not a packet sniffing real-time application. If you want to be alerted at any one point (down to a second) during a burst of traffic, you need to deploy RMON probes out to your network that can listen to traffic real-time (a few that come to mind are ntop, nGenuis, NetVigil and Nebula). MRTG is not the tool to accomplish this. ntop uses RRDTool however... Paul >>> "Meng Keng Lee" <[EMAIL PROTECTED]> 06/24/04 1:02 AM >>> Hello Alex, then how do we deploy this formula to MRTG to monitor network threshold? I did some testing and found that I did to divide by 300sec to derive a correct network utilisation percentage to be monitored for threshold alert. Furthermore, in MRTG, ThresMaxi derives its percentage from MaxBytes which is wrong then. Regards Alex van den Bogaerdt <[EMAIL PROTECTED]> wrote: On Tue, Jun 22, 2004 at 08:38:34PM -0700, Meng Keng Lee wrote: > Hello, > > Can I check with you whether the formula for calculating Network Utilisation (Input/Ouput) is correct? > > Network Utilisation (Input in %) = ifInOctets/ifSpeed * 800 > > Network Utilisation (Output in %) = ifOutOctets/ifSpeed * 800 ___if___ the ifInOctets counter counts bytes and ifSpeed is in bits then it is correct. This is __not__ the case. Both counters are of the same type (both bits or both bytes) and thus a percentage is 100 * x/y. -- Unsubscribe mailto:[EMAIL PROTECTED] 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 --------------------------------- Do you Yahoo!? New and Improved Yahoo! Mail - 100MB free storage! -- Unsubscribe mailto:[EMAIL PROTECTED] 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:[EMAIL PROTECTED] 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
