If you're not concerned about small inconsistencies and you can check counters regularly, SNMP is probably your best bet. How often can you check the counters and how often do the counters get reset? Also, is the network traffic stable, or spiky? With stable traffic and rare resets, you can just assume traffic lost in the interface reset was mean traffic. You'll come out slightly short on total packet/byte count, but with warning at 85%, it may not matter if it warns at 87% due to data loss.
Most systems that use SNMP packet count data (rrdtool, cacti, etc.) do something of this sort, AFAIK. --Ted On 4/18/2011 10:20 PM, Dan Foster wrote: > Friends from university days asked me an intriguing question the other day. > > How would you configure either Nagios or Zabbix to monitor how much data > has flowed through a particular Ethernet interface for, say, the past 31 > days? > > I guess the idea is to set an alarm if they start to approach 85% (or > whatever number) of that threshold to avoid need to pay excess bandwidth > charges. > > I assist, free of charge, on my own time as they provide a valuable > service free to the community. And, well, they're good guys, too. :) > > But how to do that? I haven't looked closely yet but still mulling it over. > > The standard bandwidth monitoring plugins in both monitoring systems > appears to be a snapshot / moment-in-time, e.g. xx Mbps, rather than a > total byte count over x days. > > Total byte count over x days also implies need to track state and counts... > > SNMP is a logical approach but the major flaw is that when snmpd is > restarted (whether by reboot or otherwise), interface counters are reset. > > Any easy way to do that, or are these folks looking at a more involved > solution of some sort? > > Any comments (snarky or otherwise :-) ) immensely appreciated! > > -Dan > > P.S. I'm very familiar with writing Nagios plugins, mostly in sh but > sometimes perl. Zabbix, not as familiar, but have set it up before. > _______________________________________________ > Tech mailing list > [email protected] > https://lists.lopsa.org/cgi-bin/mailman/listinfo/tech > This list provided by the League of Professional System Administrators > http://lopsa.org/ > _______________________________________________ Tech mailing list [email protected] https://lists.lopsa.org/cgi-bin/mailman/listinfo/tech This list provided by the League of Professional System Administrators http://lopsa.org/
