Incorrect speed display in realtime port graph

Hi all,

I’ve installed LibreNMS 1.59 and I also noticed there have incorrect speed displayed on the realtime port graph when I using less than 5 seconds polling, and it’s normal for 5s polling.

In below screenshot, I can see the speed is more then 10Gbps on 10G interface, but the real traffic is around 150Mbps.

Does anyone know how to fix this issue?

Please check out this doc
https://docs.librenms.org/Extensions/RRDTune/

Speed is also incorrect for me after tuning

It seems that 15s polling is correct

I think the page does not get the info on time and extrapolate to 5s

The counter values are then for more than 5s

Hi everybody,

I’m experiencing the same issue you reported only on Cisco IOS XR devices. On a legacy CISCO switch/router the issue is not present. By the way, I already run RRDTune setup. Any additional idea?

Thanks,
A.

Hi.
It really depend on the device (how it counts, how often the counters are updated, and how fast it replies), the network (how big is latency compared to polling interval).
Long answers short : you’ll have to try and see the shorter interval that gives correct results .

I’m experiencing the same issue you reported only on Cisco IOS XR devices. On a legacy CISCO switch/router the issue is not present.

Same issue with Juniper MX and EX series routers/switches. 5s and above seem fine, 2s and below are WAYYY off. Not that big of a deal, just wanted to add to the conversation.

Agreed. Using this on Juniper MX series routers and have the same issue.

I’m having the same issue with a few VMs Windows Server 2012 R2 on Vmware.