On Tue, May 27, 2003 at 12:54:47PM +0200, Michael Markstaller wrote: > Just a quick question, I have to monitor a 3Com Superstack 4900 GE-switch > which seems to have no SNMP-v2c at all and so no 64Bit-counters ifHC*Octets. > So far so bad, I understand the whole problem; when traffic hits 114 MBit, > counters wrap etc..
The problem is slightly different: above 114 Mbps and with a 5-minute interval, the wrapping occurs so often that mrtg doesn't find a wrap. counter increase real value seen increase 10 12 2 2+2^32 14 2 2+2^32 By polling more often, this happens: counter increase real value seen increase 10 11+2^31 1+2^31 1+2^31 (extra poll) 12 1+2^31 1+2^31 13+2^31 1+2^31 1+2^31 (extra poll) 14 1+2^31 1+2^31 Polling more often introduces more error. Suppose the timing accuracy is 1 second. Normally this results in an error of ~ 1:300. If you're going to poll every 1 second then this results in an error of 1:1. Not good. Specifying an interval of 300 seconds in rrdtool and polling every minute (or so) will work and should result in better handling of the frequent wraps but do keep the error in mind. cheers, Alex -- 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