BAARDA, Don wrote: > > > > You can define you archive as DERIVE with minimum value of 0. It > > will take care of the problem. > > > Where did this idea come from? The _best_ solution is to set a > proper max.
Nope. That is a workaround to ignore problems. The best solution is to detect wraps AND resets. The next best thing is to ignore wraps and resets. That is the derive thingy. Having a proper MAX does protect you from idiotic spikes but it does not protect you from, for instance: counter at 2^32-3750000000 wait 300 seconds counter now at 0 (after a reset, not a wrap) delta == 0 - (2^32-3,750,000,000) ==> negative add 2^32 ==> delta = 3,750,000,000 delta time == 300 -> Bps == 12,500,000 bps == 100,000,000 The proper max for this interface is set to 100Mbps so the delta is valid and thus not ignored. Voila, there you have an error. For interfaces normally not carrying a lot of traffic, ignoring an occasional REAL wrap is no big deal. Incrementing that same counter from 2^32-3,750,000,000 to 2^32 may take a long time and thus a large window for error. cheers, -- __________________________________________________________________ / [EMAIL PROTECTED] [EMAIL PROTECTED] \ | 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:[EMAIL PROTECTED] Help mailto:[EMAIL PROTECTED] Archive http://www.ee.ethz.ch/~slist/rrd-users WebAdmin http://www.ee.ethz.ch/~slist/lsg2.cgi
