Performance Graphs - ignore values?

[jacek]

Is it possible for mrtg to drop some given data?
I have one user that is complaining about peaks in graphs, like we are expecting bandwidth max ~10Mbits but sometimes we get peaks around 50 Mbits.
So the user would like to get such reads from the switch dumped.

I know this sounds weird, but that is the case...

[kyang]

There is no way out of the box to actually drop specific data points.

It would only be to delete all the data and start fresh.

Is there a reason why you want to achieve this?

[jacek]

Maybe a way to copy the check in nagios and script something around it?
I might be able to do that my self, but I don't know where to start.

Giving the upper limit in one of the arguments would be a good idea and then if something goes above for example 20Mbit just return a value of 20Mbits.

I'm not a fan of this solution at all, recommended checking what is going on in their network, but I sorta have no choice...

[npolovenko]

@jacek, Here's how bandwidth check works in XI:
1. The MRTG daemon collects the data from a switch/router and saves it into the rrd file in /var/lib/mrtg/
2. Nagios plugin (check_rrdtraf for bandwidth) renders that RRD and brings the output to the user interface.

So if you want to modify the way Nagios renders the RRD info, you could technically clone the check_rrdtraf plugin from the /usr/local/nagios/libexec/ folder, modify the source code => create a conditional statement inside, then create another command in CCM to use the new plugin instead.