Ethernet Traffic



I’ve seen ethernet traffic on this site: (guest, guest). but i can’t find plugin what i can use for it. Is somebody know what plugin are they using? (are they using snmp or something else? )

thank you!


It looks to me like they are using SNMP to query their switch for traffic data on certain switchports, but they made their own script that runs check_snmp and queries input and output kbytes/sec at the same time, and then changes the outgoing traffic value to a negative value. That way when your nagios to RRD script gets a hold of it, you can define the negative value as outgoing traffic and the positive value as incoming traffic and make a pretty graph. Lots of people just overlap incoming and outgoing traffic, these guys had a good idea. With their way you get the outgoing going downwards (negative) and the incoming going upwards when it is graphed.

To get the check data into an RRD file, they are using n2rrd which is a perl script that grabs nagios check data and puts it into an rrd file. To display that RRD with pretty colours and legend and stuff, they are using rrd2graph.

Another way to grab traffic information would be to use something like iptraf on the server itself you want bandwidth info from, and then parsing output from there.


Dear MP!
Thank you! It took me closer to the success :). Is it normal anyway that if i query my interface with snmp i get the information only with delay and sometimes i don’t get any information or maybe i have some misconfiguration with the snmpd?


I get that sometimes too with force10 switching equipment. it doesn’t happen to me on cisco. I haven’t figured out why it happens because it’s not a timeout, it just doesn’t return info.
Is yours a timeout? you can set a timeout value using check_snmp with --timeout=‘20’ for 20 seconds. If you do this, remember to change your nagios service check timeout as well.