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SNMP charts show MBytes not Mbits
Posted: Mon Mar 07, 2016 3:03 pm
by rbuckle
I am running Mikrotik routers at the front end of my network, the router/switch charting's legend show Mbps but the stats are not Mbps.
Our front door routers routinely have 500-700Mbp running through them at all times but the charting is only showing 100-200 of traffic. All i can surmise form the statistics is that the actual number could be MBits instead, that would make the number on the charts more credible.
Does anyone have any thoughts?
I am using the hypervisor VHD image of nagios.
Re: SNMP charts show MBits not Mbps
Posted: Mon Mar 07, 2016 3:37 pm
by bwallace
What type of check are you running against these devices?
For example, check_snmp would just return the value for the oid in question, unaltered, meaning you would have to verify the format the devices send the info in.
Or, are you using a plugin that is specifically intended for bandwidth-type of data, such as this?
https://exchange.nagios.org/directory/P ... h3/details
Re: SNMP charts show MBits not Mbps
Posted: Mon Mar 07, 2016 4:03 pm
by rbuckle
I am using the Default check_xi_service_mrtgraf that is created when using the Switch/Router wizard.
I am pretty new to Nagio so Sorry if i sound stupid, i am still learning
Re: SNMP charts show MBits not Mbps
Posted: Tue Mar 08, 2016 11:28 am
by bwallace
I don't know of any 'know-it-alls' (well maybe in their own minds) so hey we're all learning, right?
I used the Switch/Router Wizard here and once there was enough data to report on, I could see that the report is Mb/s - so I'd have to say your theory is correct.
Hope this helps, but certainly let us know if you have any other questions.
Re: SNMP charts show MBits not Mbps
Posted: Tue Mar 08, 2016 11:32 am
by bwallace
To clarify, I ran a 'Bandwidth Usage Report' for one of the ports.
Re: SNMP charts show MBits not Mbps
Posted: Tue Mar 08, 2016 12:20 pm
by bwallace
I was curious so I ran another test. I configured an additional switch but during step 2 of the Wizard set-up for Switch / Router, I specified bandwidth to be in kbps for this second switch (see scrnsht), where the 1st switch was left to the default of mbps.
After awhile a I ran a report for the 2nd switch and the output was in kbps.
Conclusion = the unit of measure in the report will be consistent with the unit of measure specified during step two of the set-up.
Re: SNMP charts show MBits not Mbps
Posted: Tue Mar 08, 2016 1:01 pm
by rbuckle
So can you think of a way that I can have my Nagios be in Mbits not Mbytes... to confirm, i work for a ISP so all measures are in bits...
Any Ideas?
Re: SNMP charts show MBits not Mbps
Posted: Tue Mar 08, 2016 2:01 pm
by bwallace
I'm pretty sure like you already have it in Mbits (Mbps) as there is not an option in the Nagios XI Switch/Router Wizard for Megabytes per second. (MBps).
The options are Gbps, Mbps, kbps, bps.
BTW, when it comes to bandwidth reporting / monitoring, Nagios has another product dedicated just for such. Since you work for an ISP maybe this would be more suitable, at least in this scenario?
https://www.nagios.com/products/nagios- ... -analyzer/
Re: SNMP charts show MBits not Mbps
Posted: Tue Mar 08, 2016 2:23 pm
by rbuckle
If it is in Mbits then the math is way off... the router itself is reporting a lot higher ie. 8x the amount... it must have an incorrect legend, ie. does not know that it is pulling a number that is MBytes so it assumes Mbits
Re: SNMP charts show MBits not Mbps
Posted: Tue Mar 08, 2016 3:40 pm
by ssax
I've updated the script for you to output the proper data in bits (B/b=bps; K/k=Kbps; M/m=Mbps; G/g=Gbps):
check_rrdtraf_custom.zip
NOTE: You will need to delete the RRDs that you currently have for these checks /usr/local/nagios/share/perfdata/HOSTNAME/SERVICENAME.rrd
You will lose the current data that you have for the graphs (not the original MRTG RRDs but the ones used in the interface).
Please test it out and validate the data before implementing in production.