Router Counter vs Graph Data

[andre123]

It would seemt that the is a difference between Cacti and the show interface counters on my router. The problem is with the current value. Cacti seems to be averaging everything including the last valueit reads from the router when it graphs it.

Ex. Router: 5Mb/s Cacti graphs 1Mb/s after the average.

How can I fix this so cacti graphs the last value read from the router without averaging it out. I want the avg's for monthly and yearly etc.. but not daily

[icetrain]

Think about it this way

ifSpeed = 5Mb/s

10:00 0% utilization
10:02 0% utilization
10:03 100% utilization
10:03 - 10:04 This is where you check the interface counters
10:04 0% utilization
10:05 0% utilization
10:05 - 10:06 Cacti grabs the OID, takes the value / 300 (5min) and ends up with 1Mb/s average usage for those 5 minutes

This is how RRDTool works, and was design to work.
If you want more accurate data i would suggest using shorter poll cycles, like every minute.

/Christian

[robsweet]

As a note, I don't think that the current version of Cacti deals with polling intervals != 5 minutes.

But never fear - the new version will (assuming that we can get Spine development rolling again).

Rob.

[icetrain]

For the brave:

With some changing in the database, 3-4 php files and the crontab entry you can get it working with != 5 minute intervals

/Christian

[robsweet]

Well, yeah, I meant 'as Cacti comes'. With hacking you can make it do robust, distributed polling. Hmm.....

Rob.