On Mon, Mar 19, 2007 at 09:31:42AM -0400, Dan Cech wrote: > Westlake, Simon wrote: > > In my gig test yesterday, I was hitting between 930 and 970 megs per > > second on the packet generator, and the 5 minute input/output rate on > > the switch interface confirmed this to be accurate. However, my graphs > > show anywhere between 100 and 115 megs. At first, I wondered if it was > > some type of 'MaxBytes' problem in MRTG, so I changed that value to a > > very large amount and it didn't rectify it. I then realized that 115 > > megabytes was ~964 megabit. > > Simon, > > ~115Mbps is also around the point where you'll max out 32bit SNMP > counters with a 1 minute polling interval, as you'll have multiple > rollovers per minute. > > Are you using 32bit or 64bit (SNMPv2c ifHCInOctets & ifHCOutOctets) > counters? If you're not using 64bit counters I'd recommend switching to > them and suspect it would solve your problem.
Almost agree, except that this happens with a 5 minute polling interval: 2^32 = 4294967296 4294967296 bytes / 300 seconds = 14316557 bytes per second (Bps) 14316557 Bps * 8 bits per byte = 114532456 bits per second (bps) Temporarily switching to a one minute polling interval (I think you can keep "step" to 300, no problem): 2^32 = 4294967296 4294967296/60 = 71582788 71582788*8 = 572662304 -> able to monitor 570 Mbps This buys you some time to see if and how you can use the HC counters. HTH -- Alex van den Bogaerdt http://www.vandenbogaerdt.nl/rrdtool/ _______________________________________________ rrd-users mailing list [email protected] https://lists.oetiker.ch/cgi-bin/listinfo/rrd-users
